Image Sharpness

Posted on April 16, 2015 by Andrew Astbury

Image Sharpness

I spent the other afternoon in the Big Tower at Gigrin, in the very pleasant company company of Mr. Jeffrey “Jeffer-Cakes” Young. Left arm feeling better yet Jeff?

I think I’m fairly safe in saying that once feeding time commenced at 3pm it didn’t take too long before Jeff got a firm understanding of just how damn hard bird flight photography truly is – if you are shooting for true image sharpness at 1:1 resolution.

I’d warned Jeff before-hand that his Canon 5Dmk3 would make his session somewhat more difficult than a 1Dx, due to it’s slightly less tractable autofocus adjustments. But that with his 300mm f2.8 – even with his 1.4x converter mounted, his equipment was easily up to the job at hand.

I on the other hand was back on the Nikon gear – my 200-400 f4; but using a D4S I’d borrowed from Paul Atkins for some real head-to-head testing against the D4 (there’s a barrow load of Astbury venom headed Nikon’s way shortly I can tell you….watch this space as they say).

Amongst the many topics discussed and pondered upon, I was trying to explain to Jeff the fundamental difference between ‘perceived’ and ‘real’ image sharpness.

Gigrin is a good place to find vast armies of ‘photographers’ who have ZERO CLUE that such an argument or difference even exists.

As a ‘teacher’ I can easily tell when I’m sharing hide space with folk like this because they develop quizzical frowns and slightly self-righteous smirks as they eavesdrop on the conversation between my client and I.

“THEY” don’t understand that my client is wanting to achieve the same goal as the one I’m always chasing after; and that that goal is as different from their goal as a fillet of oak-smoked Scottish salmon is from a tin of John West mush.

I suppose I’d better start explaining myself at this juncture; so below are two 800 pixel long edge jpeg files that you typically see posted on a nature photography forum, website or blog:

image sharpness, Andy Astbury, Wildlife in Pixels, Red Kite

IMAGE 1. Red Kite – Nikon D4S+200-400 f4 – CLICK IMAGE to view properly.

Click the images to view them properly.

IMAGE 2. Red Kite – Nikon D4S+200-400 f4 – CLICK IMAGE to view properly.

“THEY” would be equally as pleased with either…..!

Both images look pretty sharp, well exposed and have pretty darn good composition from an editorial point of view too – so we’re all golden aren’t we!

Or are we?

Both images would look equally as good in terms of image sharpness at 1200 pixels on the long edge, and because I’m a smart-arse I could easily print both images to A4 – and they’d still look as good as each other.

But, one of them would also readily print to A3+ and in its digital form would get accepted at almost any stock agency on the planet, but the other one would most emphatically NOT pass muster for either purpose.

That’s because one of them has real, true image sharpness, while the other has none; all it’s image sharpness is perceptual and artificially induced through image processing.

Guessed which is which yet?

IMAGE 1 at 1:1 native resolution – CLICK IMAGE to view properly.

Image 1. has true sharpness because it is IN FOCUS.

IMAGE 2 at 1:1 native resolution – CLICK IMAGE to view properly.

And you don’t need glasses to see that image 2 is simply OUT OF FOCUS.

The next question is; which image is the cropped one – number 2 ?

Wrong…it’s number 1…

Image 1 uncropped is 4928 pixels long edge, and cropped is 3565, in other words a 28% crop, which will yield a 15+ inch print without any trouble whatsoever.

Image 2 is NOT cropped – it has just been SHRUNK to around 16% of its original size in the Lightroom export utility with standard screen output sharpening. So you can make a ‘silk purse from a sows ear’ – and no one would be any the wiser, as long as they never saw anything approaching the full resolution image!

Given that both images were shot at 400mm focal length, it’s obvious that the bird in image 1 (now you know it’s cropped a bit) is FURTHER AWAY than the bird in image 2.

So why is one IN FOCUS and the other not?

The bird in image 1 is ‘crossing’ the frame more than it is ‘closing in’ on the camera.

The bird in image 2 is closer to the camera to begin with, and is getting closer by the millisecond.

These two scenarios impose totally different work-loads on the autofocus system.

The ability of the autofocus system to cope with ANY imposed work-load is totally dependent upon the control parameters you have set in the camera.

The ‘success’ rate of these adjustable autofocus parameter settings is effected by:

Changing spatial relationship between camera and subject during a burst of frames.
Subject-to-camera closing speed
Pre-shot tracking time.
Frame rate.

And a few more things besides…!

The autofocus workloads for images 1 & 2 are poles apart, but the control parameter settings are identical.

The Leucistic Red Kite in the shot below is chugging along at roughly the same speed as its non-leucistic cousin in image 2. It’s also at pretty much the same focus distance:

Image 3. Leucistic Red Kite – same distance, closing speed and focal length as image 2. CLICK IMAGE to view larger version.

So why is image 3 IN FOCUS when, given a similar scenario, image 2 is out of focus?

Because the autofocus control parameters are set differently – that’s why.

FACT: no single combination of autofocus control parameter settings will be your ‘magic bullet’ and give you nothing but sharp images with no ‘duds’ – unless you use a 12mm fish-eye lens that is!

Problems and focus errors INCREASE in frequency in direct proportion to increasing focal length.

They will also increase in frequency THE INSTANT you switch from a prime lens to a zoom lens, especially if the ‘zoom ratio’ exceeds 3:1.

Then we have to consider the accuracy and speed of the cameras autofocus system AND the speed of the lens autofocus motor – and sadly these criteria generally become more favourable with an increased price tag.

So if you’re using a Nikon D800 with an 80-400, or a Canon 70D with a 100-400 then there are going to be more than a few bumps in your road. And if you stick to just one set of autofocus control settings all the time then those bumps are going to turn into mountains – some of which are going to kill you off before you make their summit….metaphorically speaking of course!

And God forbid that you try this image 3 ‘head on close up’ malarkey with a Sigma 50-500 – if you want that level of shot quality then you might just as well stay at home and save yourself the hide fees and petrol money !

Things don’t get any easier if you do spend the ‘big bucks’ either.

Fast glass and a pro body ‘speed machine’ will offer you more control adjustments for sure. But that just means more chances to ‘screw things up’ unless you know EXACTLY how your autofocus system works, exactly what all those different controls actually DO, and you know how to relate those controls to what’s happening in front of you.

Whatever lens and camera body combination any of us use, we have to first of all find, then learn to work within it’s ‘effective envelope of operation’ – and by that I mean the REAL one, which is not necessarily always on a par with what the manufacturer might lead you to believe.

Take my Nikon 200-400 for example. If I used autofocus on a static subject, let alone a moving one, at much past 50 metres using the venerable old D3 body and 400mm focal length, things in the critical image sharpness department became somewhat sketchy to say the least. But put it on a D4 or D4S and I can shoot tack sharp focussing targets at 80 to 100 metres all day long……not that I make a habit of this most meaningless of photographic pastimes.

That discrepancy is due to the old D3 autofocus system lacking the ability to accurately discriminate between precise distances from infinity to much over 50 metres when that particular lens was being used. But swap the lens out for a 400 f2.8 prime and things were far better!

Using the lens on either a D4 or D4S on head-on fast moving/closing subjects such as Mr.Leucistic above, we hit another snag at 400mm – once the subject is less than 20 metres away the autofocus system can’t keep up and the image sharpness effectively drops off the proverbial cliff. But zoom out to 200mm and that ‘cut-off’ distance will reduce to 10 metres or so. Subjects closing at slower speeds can get much closer to the camera before sharp focus begins to fail.

As far as I’m concerned this problem is more to do with the speed of the autofocus motor inside the lens than anything else. Nikon brought out an updated version of this lens a few years back – amongst its ‘star qualities’ was a new nano-coating that stopped the lens from flaring. But does it focus any faster – does it heck! And my version doesn’t suffer from flare either….!

Getting to know your equipment and how it all works is critical if you want your photography to improve in terms of image sharpness.

Shameless Plug Number 1.

I keep mentioning it – my ebook on Canon & Nikon Autofocus with long glass.

Understanding Canon & Nikon Autofocus

for

Bird in Flight Photography

Click Image for details.

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Lumenzia for Easy Luminosity Masking

Posted on March 9, 2015 by Andrew Astbury

Lumenzia for Easy Luminosity Masking..

I’m a really BIG user of luminosity masking techniques, and the ease by which you can use them to create really powerful adjustments to your image inside Photoshop – adjustments that are IMPOSSIBLE to make in Lightroom.

For a while now I’ve been selling a luminosity mask action set for Photoshop, and up until a week ago I had plans to upgrade said action set to produce even more custom masks.

That is until a good friend of mine, Mr. Omar Jabr, asked me if I’d come across this new product, LUMENZIA, that made the production and deployment of luminosity masks and their derivatives EVEN EASIER.

Lumenzia,luminosity masking,Andy Astbury,Wildlife in Pixels Blog

An original RAW file open in Lightroom (right) together with the final image (left) – 99% of the “heavy lifting” being done in Photoshop using the Lumenzia Extension and it’s luminosity masking functions.

In all honesty I am so excited about this amazing software extension that I’ve abandoned all plans to further develop my own action set for Photoshop – to do so would be a truly pointless exercise.

There is so much more to Lumenzia than the production of the standard 4 or 5 Darks,Lights and Midtone luminosity masks that mine and other available action sets produce.

To get an idea of just how powerful Lumenzia is just click HERE to visit the applications home page – and just buy it while you are there; purchase is a “no brainer” and one of those digital imaging JDI’s (just do it)!

The inclusion of a luminosity masking function based on the Zone System gives you instant recourse to masks based on Ansel Adams 11 zone system of scene brightness – a classic approach to the quantification of subject brightness range created by arguably the greatest landscape photographer the world has ever known – IMHO of course.

In order to instal Lumenzia you will need to install the correct Photoshop Extension Manager for which ever version of Photoshop you are running – CS6, CC, or CC2014 (it is not intended to be installed on CS5 or lower).

1. Buy Lumenzia

2. Follow the download link, and download the .Zip folder.

3. Extract the folder contents.

4. Locate the “com.lumenzia.zxp” file in the extracted contents, right click and choose Open with: Adobe Extension Manager v.xx

You should see:

Click Install, and you should see:

If you are running Mac OS 10.10x Yosemite you may have a slight problem with the CC2014 Extension Manager not being able to find the application pathway to Ps CC2014. If you get a message from the Extension Manager waffling on about needing Photoshop v11 or higher don’t stress, the fix is a little brutal but really simple:

Go Applications>Utilities>Adobe Installers and UNINSTALL (that’s right!) BOTH Photoshop CC2014 and Extension Manager CC2014, then log back in to your CC account, go to the Apps tab and re-install Photoshop CC2014 AND Extension Manager CC2014 sequentially – that will cure the problem and only take about 5 or 6 minutes.

Open a RAW file in CameraRAW, or better still Lightroom. Get your camera calibration and contrast under control as I’ve banged on about so many times before, negate any chromatic aberration and do a bit of effective noise reduction if needed, then send the image to Photoshop:

Go Window>Extensions>Lumenzia

Go Window>Extensions>Lumenzia and the Lumenzia interface will appear – I like to drag it into the right hand tools palette so it’s not encroaching on the work area.

The first thing that amazed me about Lumenzia is the fact that you can create luminosity masks without creating 12 or 15 separate Alpha channels with the image – this makes a HUGE difference to the file size of the image, not just from the disc space PoV but it can also have file handling speed benefits in terms of tile rendering speed and scratch disc usage – if you don’t understand that just think of it as a GOOD thing!

For example:

The final adjusted image (prior to a couple of tweaks in Lightroom) on the left is 271Mb including all layers being intact; the image on the right, though not yet processed, has been prepared for processing by running a luminosity mask action set and developing a stack of Alpha channels; it is now over 458Mb:

…just because of the Alpha channels. And we have also got 50 steps of History that have to be retained by Photoshop; as you’ve now realised, the joke is that it’s double the size of the Lumenzia processed image and we haven’t begun to start making any adjustments yet!

There is lot’s more to Lumenzia, such as surface sharpening and easy dodge and burn layer creation – it’s going to take me a week to digest it all.

Prior to working with Lumenzia my one question was “how good are the masks” – well they are pixel-perfect.

Creating pixel-perfect luminosity masks is the most tedious of jobs if you do it the maual way – so much so that most folk take one look at the process and go “No thanks…..”

Photographers like myself couldn’t really help alleviate the tedium until the advent of CS6 which gave us the ability to write an ACTION that involved the operation of a PREVIOUSLY recorded action – so the luminosity mask action set was born.

But the developer of Lumenzia has topped it all by the proverbial country mile and given us a totally unique way of making the tedious and complex very easy and simple.

Once you have made your purchase you’d do well to go and watch the developer videos that are available online; you will get links to the training and support pages in your purchase receipt.

And to top it all off we can even generate Alpha channels and selections if we want or need to, and we can mask on the basis of Vibrancy and Saturation; yet another processing wheeze known by few, and used by fewer still.

The developer has given me permission to demonstrate and teach the deployment of Lumenzia, and to promote it as an affiliate. I’ve been offered affiliate-ships before but have rejected them in the past because basically what was being peddled was either crap or too expensive; or BOTH.

But whatever you think the opinion of yours truly is worth, I can honestly say that Lumenzia is most definitely NEITHER of the above – it’s that good I’ll never use anything else ever again, and at under 40 bucks you’re going to make one hell of a difference to your images with so little effort it’s unreal.

Click HERE to buy and download

LUMENZIA – BUY IT – go on, get on with it!

Lumenzia GUI for Photoshop CC2014

UPDATE June 2018: Greg Benz (the plugin author) has launched a comprehensive Lumenzia training course – see my post here for more information.

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Canon 1Dx & 200-400 f4 L IS USM

Posted on March 3, 2015 by Andrew Astbury

A Nikon users thoughts on using the Canon 1Dx and the 200-400 f4L IS USM.

The Canon 200-400 f4 L IS USM on the 1Dx – overall a staggeringly good pairing that I’m really going to miss when I have to give it back!

For years now, my “standard” wildlife photography lens has been the only 200-400f4 that was ever available, the Nikon.

An epic lens; sharp, good resolution in terms of line pairs per millimetre, and most importantly a boon to in-camera composition. It makes an excellent job of everything I ever ask it to do, from cute Red Squirrels 2 metres in front of me, to thumping great Norwegian Sea Eagles barreling towards me at thirty miles per hour and 30 metres out.

However; it’s not without it’s little idiosyncrasies, in fact I often describe it as “a pig” of a lens to use. Sharpness at 50 meters is questionable, and beyond 75 metres is pathetic – the bottom of a milk bottle could do better.

And it hates teleconverters as a rule – yes it’s sharp, but the resolution drops through the floor.

But if you wanted the compositional versatility that only a 200-400 can give you, then you had no option but to shoot Nikon.

Until that is, the day Canon did the unthinkable and launched their version of a 200-400 f4. And they gave it an internally switch-able 1.4x teleconverter giving you an effective 200 f4 to 560 f5.6 working range – WOW!

I first got hold of one of these babies about 4 weeks after they became available; a client at a Drummond Street workshop I was doing for Calumet brought it in stuck on the front of a 1Dx. I’d torn the lens from his poor hands before he knew what was happening, and whipped it outside, stuck the 1Dx in AF case 2, auto iso, 10 frames per second, manual exposure at 1/2000th and f6.3 and began rattling off frames of passing traffic – I was astounded by the lenses performance.

Over the following 18 months I had one or two further opportunities to “have a bash” with the 1Dx + 200- 400 combo, and it honestly impressed the “bejesus” out of me every time; so much so that I’ve recommended any Canon user that asked me to just BUY ONE. And buy one they did!

I’d also had access to a raft of CR2 raw files shot with this combo from one or two other photographers “who know what they are doing”; especially from my old pal Steve “Judith Chalmers” Kaluski of Untamed Images.

As many folk know, I run Eagle Photography workshop tours to Norway every now and again, and with a winter workshop in February 2015 coming up I was thinking that 200mm to 560mm would make this lens perfect for Norway.

Seeing as I “sold” half a dozen of these lenses for Canon I reckoned they owed me a favour – big time.

So I had a word in a few ears at Calumet, and Reece Piper kindly sent me a 1Dx on loan. Canon UK were not quite so forthcoming – basically saying they hadn’t the stock availability to lend me one for upwards of a month. But my favourite Geordie Lass June Lown came to the rescue and volunteered her newly acquired 200-400, bought on the recommendation of yours truly, for the testing and trip to Norway.

So the scene was set for an epic journey into the inner workings of the lens and the 1Dx you have to hang off the back of it in order to get the “best?” out of it.

Testing & Evaluation

Back in the days of yore, when we all shot film, lenses were tested on a full optical test bench, and the MTF charts produced thusly actually meant something. If the lens tested good, but you got soft images you KNEW you had a camera body lens mount problem, or that the pressure plate that held the film in the proper plane was distorted.

But now, certain manufacturers don’t even measure MTF – they use a calculator to work them out based upon theoretical values NOT real ones. And then we have entities like DXO Labs, who test lenses on cameras. This is lunacy if you are wanting to know about TRUE LENS performance, simply because the quality of lens output (the image projected into the sensor plane) is effected by the vagaries of the item that lives there – the sensor!

And on top of that, when testing under non-laboratory conditions, the performance of the lens is further clouded by inaccurate or unsuitable camera settings, especially those pertaining to auto focus.

So field testing of lenses is not simply a case of “point – squirt – evaluate”; it has to be done with more than a modicum of intelligence when it comes to camera AF settings. You have to do TWO things:

1. UNDERSTAND COMPLETELY how the AF system works and what the parameter control adjustments actually do.

2. Evaluate your subjects behaviour in terms of the aforementioned parameters and adjust them accordingly.

You may be interested in acquiring, for a small fee, my pdf guide to Long Lens Autofocus for Canon & Nikon systems.

Previous experience with the 1Dx had led me to treat the camera with a little trepidation for one single reason – its sensor. As a Nikon user I am used to working with sensors which have perhaps the highest Dynamic Range, lowest Base Noise, and highest Signal-to-Noise (S/N) ratios of any popular 35mm format camera body.

On the left is a Canon 1 Dx CR2 file, right is a Nikon D4 NEF file. Both images were shot at identical ISO, aperture, Ev comp and shutter speed within milliseconds of each other on a dual camera rig. The birds cheek patches are “blown” on the CR2, but the highlight detail is all there in the Nikon file.

This is indicative of the shorter Dynamic Range of the 1Dx sensor. The common perception is that the Nikon D4/4s sensors have roughly 1.5 stops greater dynamic range than the Canon 1Dx – this in effect means that the Nikon speed machine can cope with a least DOUBLE the subject brightness range that the 1Dx can handle.

Note: I find enabling Highlight Tone Priority, shooting menu tab 2 setting D+, does NOT sort the problem out in high contrast situations like this – it just gives you problems with the darker tones in the image.

So are there any other “sensor vagaries” on the Canon 1Dx that can effect the overall image quality – you betcha there is…

When I picked the camera up from Calumet I also “accrued” the 100mm f2.8 L macro lens, specifically to test the sensor base noise levels on a studio hi-speed flash shot I wanted to do. I had already done the setup shots the day before on the Nikon D4, as part of my drive to show single-body owners how versatile they can be with their photography.

You can read my article on the 1Dx sensor noise HERE

Canon 1Dx + 100mm f2.8 macro. Nikon SB800 flash & Calumet ProSeries wireless.

The original CR2 file looks like this (left) and the Nikon setup shot is on the right:

But if we open the images in Photoshop and use a standing wave curves layer over the top of them – as we would do when retouching the images – we see the extreme pattern noise in the 1Dx sensor (above), while we have virtually none in the Nikon file.

We can see more clearly the pattern noise in the 1Dx sensor if we view the images at 100% magnification.

Custom Curve layer at 100% – now that pattern noise on the Canon sensor is obvious.

We can derive from this shoot/test that the Canon 1Dx is a bit more “photon-hungry” than your average Nikon pro body sensor, but then doesn’t have the dynamic range capability to cope with lots of photons when it sees them.

Now let’s be real about all this for a moment; the 1Dx sensor is old tech in all fairness to Canon, though I’ll counter that by throwing the venerable Nikon D3 into the argument – that body is older than a 1Dx and has a sensor that performs far better in both dynamic range and base noise departments.

In reality though, the pattern noise, though always present in 1Dx images, is usually hidden or masked by actual image/subject detail so that, for the most part, you don’t see it AT ALL – just don’t try going for low ISO when photographing the “Black Cat in the Coal House at Midnight”, with a 1Dx if you have an aversion to heavy Photoshop work.

As I said before, as a Nikon user, the sensor output of the 1Dx leaves me grimacing a little to say the least. But, climbing back on the fence of neutrality I can see that dedicated Canon users might not notice the problems I see if only on the basis of “what you’ve never had you never miss”.

And as I was to discover, there’s something of a bonus with this sensor that this Nikon user was not expecting…..more later.

The ongoing banter between Nikon and Canon users is all very well, and usually good for a bit of a laugh between fellow photographers BUT, the reality is this – ALL pro level 35mm format camera bodies from either Canon or Nikon have their good points and bad points; and not a single one stands head- and-shoulders above the rest ON ALL COUNTS.

“What the Lord giveth with one hand, he taketh away with the other” is definitely the one saying that springs to my mind when I get asked about cameras! If you know what you are doing it doesn’t matter which one you use, you’ll invariably find 10 things wrong with it in the first 30 minutes!

I don’t like the feel of the 1Dx – it feels like I’m holding a brick – BUT SO WHAT?
I hate the menu system – it’s mental – BUT YOU GET USED TO IT
I dislike the sensor output – BUT IT’S FIXABLE for the most part.
Buttons & button+button or dial combos – COME ON GUYS, I’m neither double jointed or gifted with four hands!

There used to be a very large version of this image on the web that sums up Canon buttons, but I can only find a small version of it now:

Sadly the “Call Spock” button will not work any more – RIP L.N.

My list of gripes and niggles about the 1Dx could go on but, sensor output notwithstanding, that list could be easily matched or exceeded by my list of niggles about Nikon cameras! So expanding on them any further is a pointless exercise.

Likewise, comparing the two 200-400s as separate lenses is a somewhat pointless activity too – they are different beasts by a country mile, and I would liken the task to attempting a comparison between the iconic Z28 Pontiac Firebird and the equally iconic Aston Martin DBS – as I said, pointless.

But I feel justified in comparing certain aspects of the camera bodies, and seeing as I have already dealt with the sensor comparison to a degree, I’ll now look at the other main fundamental difference I see between Canon and Nikon; and that is the autofocus system.

Autofocus:

I am going to make a very broad and sweeping statement now, and that is Canon autofocus is generally better than Nikon autofocus – FACT.

What do I mean by better?

I mean that it is more controllable and furnishes the user with a greater ability to tailor the autofocus to suit the behaviour of the intended subject. But the more eagle-eyed reader will have spotted my use of the word “generally”; that is there to indicate a caveat – and the caveat is this:

Only if you know what you are doing!

If you DON’T, and you start fiddling with settings such Acceleration/Declaration tracking, then you risk getting in a proper old mess and you’ll wish you HAD bought Nikon!

My soon-to-come Autofocus Guide to Nikon and Canon – available from this very boutique – goes into the nitty-gritty of autofocus in great detail – so buy it..

In a nutshell, you can tailor the Canon autofocus system to cope with how the subject moves ALONG the lens axis; that’s where your AF has to do the most work. Is it moving towards the camera at a constant speed, or is it moving towards the camera in a stop-go-slow-fast-slow manner? With the Canon 1Dx AF system you have 5 different settings you can use to cover this manner of movement. And these settings are all independent of your AF point group settings.

On a Nikon you have NO independent way of setting the camera to cope with this aspect of subject movement. Using a nine point group on a Nikon tends to favour subjects that move in a constant direction and speed, while the 21 point group favours the more erratically moving subject; which has always seemed a little silly to me and somewhat short-sighted of Nikon.

After 6 weeks of working with the 1Dx in conjunction with the 200-400mm on all manner of moving subjects in terms of size, speed and proximity to the camera I have come to the conclusion that only Cases 2 & 6 are of any real use to me as a wildlife photographer. But I have a tendency to select Case 3 and modify it in terms of Tracking Sensitivity and Acceleration/Declaration Tracking as a scene/subject presents itself.

The third parameter adjustment – AF Point Switching – for the most part I have tended to leave at the default setting of 0, though a setting of 1 has proved useful when dealing with the more erratically moving subject when you too are moving somewhat erratically, such as being in a small boat at sea.

White-tailed Eagles locking talons – 1Dx + 200-400 hand held from boat, AF Case 6, 9 point AF expansion, AF point switching +1, Manual Exposure, Auto ISO 1/2000th, f6.3 ISO 640

For the sort of work that I do within this focal length range, I would only ever use the AF Area Modes of Spot, Expanded (what I call 1 with 4 friends) and Expanded AF Surround ( 1 with 8 friends). Under NO circumstances do I want to leave the camera to decide on what part of the subject I’m focussing on, so Zone and Auto are off my radar. For the same reason I never use the 3D tracking mode on my Nikons. But having said that, I can very well envisage photographers using much shorter focal lengths benefiting from the other modes in certain circumstances due to the greater inherent depth of field they have at their disposal.

But what impresses me most is the speed of the AF using this camera and lens combination, it makes my D4 and Nikon 200-400 look like a clockwork toy; even though I always thought it was fast enough….

1Dx + 200-400 hand held from boat, AF Case 6, 9 point AF expansion, AF point switching 0, Manual Exposure, Auto ISO 1/2000th, f6.3 ISO 640

I only hit the AF activation on this bird a split second before the shot was taken – razor sharp, see for yourself:

So, I get to this juncture and have to start asking myself a couple of questions:
1. Would this shot, for instance, look even better via a Nikon D4/D4S sensor ?
2. Would I have got this particular shot using the D4 or a D4S and my Nikon 200-400?

The answer to the first question is YES – it would; there would be somewhat less noise for starters, and the extra dynamic range would at least facilitate easier processing. Being so used to NEF files I find I have to do a more delicate balancing act between highlight and shadow tones when processing 1Dx CR2 files.

Using the 1Dx I’m a lot more concious of the fact that I need to “watch” my highlights when shooting, and that when it comes to processing it’s like I’ve gone back to 12bit RAW files – and it’s years since I’ve processed one of those babies!

The answer to question 2 though is a little more problematic. Under the EXACT same circumstances the answer is most likely a NO as it was basically “snap-shot”, and that sort of shooting rarely works out too well on Nikon using an f4 lens when a fast-moving subject is right on top of you.

Using an f2.8 would have pulled this shot off under the same circumstances without a problem.

Had I framed up on this eagle 4 or 5 seconds beforehand and let the AF track it until it got to this position then YES I would have got the same result; as long as I had been in a 21 point group. But I usually don’t favour a 21 point group on Nikon because it’s just that bit harder to be precise – I want focus on the eagles eye and I couldn’t give a you-know-what about its other bits – so I usually opt for a 9 point group.

Bearing in mind that this bird is DECELERATING RAPIDLY, the Nikon 9 point group and its fixed “speed tracking preset” might allow the predictive side of the Nikon AF system to advance the focus a little closer to the camera than needed at the moment the shutter opens; because the “preset” is more geared toward a CONSTANT subject speed.

And seeing that the camera isn’t exactly stable either, being in a small boat, the new Nikon 4 point group might have made an even bigger cock-up because it always attempts to focus on the nearest point – which ISN’T the eagles eye.

It’s all about the Accel/Decel tracking…..(ADT – my acronym!)

On the 1Dx Canon give you 5 totally independent ADT settings, and Nikon give you 2 fixed presets which are enslaved to separate AF point groups.

Shooting large subjects at distance – such as football – makes for light work in terms of ADT and predictive AF due to the inherently large depth of field for any given f-number. But shoot smaller, faster moving subjects at much shorter distances and those same ADT settings will make a huge difference to the focus accuracy of the captured image.

When shooting somewhat slower moving subjects I always like to switch to a single AF point and place it over the subjects eye.

I like the Spot AF setting on the 1Dx for this sort of work, especially when I can get the composition I want using one of the centre diagonal cross-type sensors, as in this Lynx below:

1Dx + 200-400 at 400mm AF Case 2, spot AF, Manual Exposure, Auto ISO 1/250th, f7.1 ISO 1000 IS Pos 2 – just because I could!

1Dx + 200-400 at 400mm AF Case 2, spot AF, Manual Exposure, Auto ISO 1/250th, f7.1 ISO 200 IS Pos 2 – just to see HOW low I could go!

The Arctic Fox above is shot with Spot AF using a conventional cross-type sensor from the centre left column.

The Wolves below are shot with a diagonal cross-type sensor from the centre column placed over the right eye of the wolf in the middle of the shot, but this time I’m in AF point expansion – 1 with 4 friends – with AF point switching set to +1. This covers off any movement of the wolfs eye up, down, left or right and increasing the point switching from 0 to +1 means that the active Af point will switch to one of those “4 friends” in order to follow the eye if I can’t move the camera fast enough:

1Dx + 200-400 at 366mm AF Case 2, single point AF expansion, Manual Exposure, Auto ISO 1/1000th, f7.1 ISO 4000 – I’m being a bit more sensible now – if you call standing taking pictures of this pair of bad boys with nothing twixt me and them except fresh air sensible!

Canon Spot AF uses just the centre portion of the selected AF sensor and so you can do some very precise focussing using this AF mode.

Where I find it a real boon is when working off a tripod or from a hide where the camera is rock steady on some form of gimbal or ball head, as in this type of shot. And it really comes into its own when using the 1.4x built-in TC on the 200-400:

As you can see from the screen-grab below I have a single AF point selected and located exactly where I want it:

What you can’t see is that Spot AF – which I think Canon ought to re-name “precision” – is only using the centre portion (perhaps 50%) of the area marked in red; so the main focus is concentrated where the eagles beak has dug into the side of the Pine Martens head – very cute and cuddly I must say…

Autofocus Conclusion:

Nikon AF is rather “simplified” and to be honest it has served exceptionally well over the years. But the one niggle I’ve always had is that I WANT to dictate what the AF does, and how and when it does it – I loathe and detest being dictated to, especially by some algorithm written by lab tech who wouldn’t know his “arse from his elbow” when it comes to a good picture.

It’s as if those Nikon guys think I’m an idiot and they know best – it’s not true fellas!

In all fairness, they sell cameras to folk who “aspire”, and those folk need some sort of instant gratification. Also, those same folk would not do the sort of photography that I do “as norm” – yes, I AM NIKON; but I am also a minority!

So I can see why Nikon make use of “preset averages” in a lot of their control algorithms – I just wish they made pro versions of their cameras with a lot of these so-thought-of Intelligent functions left out; I for one would certainly be a lot more chilled out of they did.

Canon have always been notorious for crediting their users with more than a modicum of intelligence, yet they still give the “L plate” folk half a chance by offering certain levels of automation and presets.

As someone who uses all the facilities on a camera body close to the boundaries of their design criteria – and sometimes past ’em! – I find the 1Dx AF system fabulous in terms of both speed and tractability, and it negates all the niggles and gripes about the Nikon system that I have soon got to return to….

Unless of course some retailer, or those lovely guys at Canon take pity on me!

A Nikon Users Final Judgement on the 1Dx + 200-400mm f4 L IS USM

For the least 6 weeks I’ve been on something of a journey that’s for sure.

Strange “buttonograhy” has caused me some head-scratching! I’m a back button focus man myself, so no prizes for guessing which button has given me most confusion – that’s right, the STAR BUTTON!

My brain simply cannot retain what its function is, so when I hit it accidentally with a gloved thumb, I’ve developed a really simple remedy for getting rid of it – TURN THE CAMERA OFF then back on again! That’s a proper Andy Pandy fix that is!

When I get into situations where my subjects are moving into and out of the sun, and scene contrast changes constantly, I still adopt my preferred method of shooting, and that is FULL MANUAL with auto ISO.

The venerable Nikon D3 didn’t handle this too well; the ISO was always a “little sticky” at at coming back down to the lower numbers. The D4 is a lot better, but still comes a little unstuck from time to time.

The Canon 1Dx has performed flawlessly and has just come back from 7 days in Norway where it has been permanently in Manual Exposure with Auto ISO from the very first to the very last frame of the trip, and the Auto ISO function has performed perfectly on every frame.

Here is a situation where this method of shooting paid dividends, with one of the most rarely seen raptors on the planet – the Goshawk:

Goshawk in the rain – 1/60th sec, f5.6, Manual Exposure + Auto ISO 12800

We were in the darkest heart of a chunk of Boreal Forest, at dawn, and it was chucking it down with rain – gloomy is not a word that does the lack of light justice.

Like a ghost this male Goshawk materialises in front of us and we need to get the shots. With so little light, and the teleconverter switched in we need to pick the shots off each and every time the bird stops moving its head. So the fastest speed we can use is 1/60th sec, which on a gimbal mounted rig at 560mm is just do-able with good technique.

Slipping the IS into Mode 2 and using Spot AF continually on the Goshawks eye we got a large number of razor sharp images in the poorest light I think I have ever shot in.

Here is a 100% crop from that image:

Now considering that this image is from a sensor that I’m not overly keen on, let’s compare it to a shot on a sensor I’m usually far happier using – that of a D4S, that happened to be about 3 feet to my left and operated by a client, Mr. Paul Atkins, using the Nikon 200-400:

The same 12800 ISO, both these shots are pretty much straight from the sensor with minimal processing.

Well, I know which I prefer, and it isn’t the one done with a black lens!
A lot of folk think 400 ISO is high – well it isn’t; even though it used to be.

As I have said before in this article, the 1Dx sensor – as far as this Nikon user is concerned – is a little short in the performance stakes; but is it?

At more conventional speeds below 3200 ISO I firmly come down on the side of Nikon.

From 3200 ISO to 5000 ISO I don’t think there is much between them, but above 5000 ISO the Canon 1Dx excels by a country mile; and Nikonophilles can argue the toss with me ’til the cows come home – but I have the images to prove it – so “boo-hoo, sucks to you chaps”…

With all DSLRs, as we increase ISO we shorten Dynamic Range, but it would appear that, even though the 1Dx is shorter than a D4S in that department to begin with, it hangs on to it a lot longer – and that means more images you can make money from; or win competitions with, which ever floats your boat.

When the end of the Universe comes and it’s “lights out” for everyone, just make sure you’ve got a 1Dx in your hand – Shutterstock and Getty will rip your arm off for the shots ‘cos they’ll still be around somewhere, and God won’t get rid of them that easy!

Sadly, I’ve got to give the 1Dx back to Calumet so that they can hire it to some un-appreciative plebs and recoup the dough they’ve lost while yours truly has been jollying it up with the Vikings.

And as for the glorious 200-400, well, that’s got to go back to the lovely June Lown who loaned it to me in the first place.

So many thanks to June, and to Reece Piper from Calumet for agreeing to the long loan 1Dx, and to John Willis from Calumet Manchester for knowing everyone, and for “lubricating the gears” that make the world go around.

In closing I suppose I need to answer the question I’ve been asked a lot since word of my Canon-ising escaped into the general UK wildlife scene – am I ditching Nikon?

No is the short answer; not even if I could afford to.
BUT, if I could afford to I WOULD buy a 1Dx and 200-400 f4 L IS USM – today!

I would dump my Nikon 200-400, but keep the D4/D4S for use with a big prime. But given the choice my standard wildlife “go to” lens would be the Canon 200-400 in conjunction with a 1Dx. It would get more shots than it would lose me, and Canon can always get rid of my gripes about the sensor by upgrading it – as long as they don’t lose the superb high ISO performance.

Right, that’s it – I’m off to go curl up in a corner of my office and cry at the thought of giving this gear back to its rightful owners….

I WANT THIS RIG…do I really have to give it back?

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Camera Calibration

Posted on September 29, 2014 by Andrew Astbury

Custom Camera Calibration

The other day I had an email fall into my inbox from leading UK online retailer…whose name escapes me but is very short… that made my blood pressure spike. It was basically offering me 20% off the cost of something that will revolutionise my photography – ColorChecker Passport Camera Calibration Profiling software.

I got annoyed for two reasons:

Who the “f***” do they think they’re talking to sending ME this – I’ve forgotten more about this colour management malarkey than they’ll ever know….do some customer research you idle bastards and save yourselves a mauling!
Much more importantly – tens of thousands of you guys ‘n gals will get the same email and some will believe the crap and buy it – and you will get yourselves into the biggest world of hurt imaginable!

Don’t misunderstand me, a ColorChecker Passport makes for a very sound purchase indeed and I would not like life very much if I didn’t own one. What made me seethe is the way it’s being marketed, and to whom.

Profile all your cameras for accurate colour reproduction…..blah,blah,blah……..

If you do NOT fully understand the implications of custom camera calibration you’ll be in so much trouble when it comes to processing you’ll feel like giving up the art of photography.

The problems lie in a few areas:

First, a camera profile is a SENSOR/ASIC OUTPUT profile – think about that a minute.

Two things influence sensor/asic output – ISO and lens colour shift – yep. that’s right, no lens is colour-neutral, and all lenses produce colour shifts either by tint or spectral absorption. And higher ISO settings usually produce a cooler, bluer image.

Let’s take a look at ISO and its influence on custom camera calibration profiling – I’m using a far better bit of software for doing the job – “IN MY OPINION” – the Adobe DNG Profile Editor – free to all MAC download and Windows download – but you do need the ColorChecker Passport itself!

I prefer the Adobe product because I find the ColorChecker software produced camera calibration profiles there were, well, pretty vile in terms of increased contrast especially; not my cup of tea at all.

5 images shot at 1 stop increments of ISO on the same camera/lens combination.

Now this is NOT a demo of software – a video tutorial of camera profiling will be on my next photography training video coming sometime soon-ish, doubtless with a somewhat verbose narrative explaining why you should or should not do it!

Above, we have 5 images shot on a D4 with a 24-70 f2.8 at 70mm under a consistent overcast daylight at 1stop increments of ISO between 200 and 3200.

Below, we can see the resultant profile and distribution of known colour reference points on the colour wheel.

Here’s the 200 ISO custom camera calibration profile – the portion of interest to us is the colour wheel on the left and the points of known colour distribution (the black squares and circled dot).

Next, we see the result of the image shot at 3200 ISO:

Here’s the result of the custom camera profile based on the shot taken at 3200 ISO.

Now let’s super-impose one over t’other – if ISO doesn’t matter to a camera calibration profile then we should see NO DIFFERENCE………….

The 3200 ISO profile colour distribution overlaid onto the 200 ISO profile colour distribution – it’s different and they do not match up.

……..well would you bloody believe it! Embark on custom camera calibration profiling your camera and then apply that profile to an image shot with the same lens under the same lighting conditions but at a different ISO, and your colours will not be right.

So now my assertions about ISO have been vindicated, let’s take a look at skinning the cat another way, by keeping ISO the same but switching lenses.

Below is the result of a 500mm f4 at 1000 ISO:

Profile result of a 500mm f4 at 1000 ISO

And below we have the 24-70mm f2.8 @ 70mm and 1000 ISO:

Profile result of a 24-70mm f2.8 @ 70mm at 1000 ISO

Let’s overlay those two and see if there’s any difference:

Profile results of a 500mm f4 at 1000 ISO and the 24-70 f2.8 at 1000 ISO – as massively different as day and night.

Whoops….it’s all turned to crap!

Just take a moment to look at the info here. There is movement in the orange/red/red magentas, but even bigger movements in the yellows/greens and the blues and blue/magentas.

Because these comparisons are done simply in Photoshop layers with the top layer at 50% opacity you can even see there’s an overall difference in the Hue and Saturation slider values for the two profiles – the 500mm profile is 2 and -10 respectively and the 24-70mm is actually 1 and -9.

The basic upshot of this information is that the two lenses apply a different colour cast to your image AND that cast is not always uniformly applied to all areas of the colour spectrum.

And if you really want to “screw the pooch” then here’s the above comparison side by side with with the 500f4 1000iso against the 24-70mm f2.8 200iso view:

500mm f4/24-70mm f2.8 1000 ISO comparison versus 500mm f4 1000 ISO and 24-70mm f2.8 200 ISO.

A totally different spectral distribution of colour reference points again.

And I’m not even going to bother showing you that the same camera/lens/ISO combo will give different results under different lighting conditions – you should by now be able to envisage that little nugget yourselves.

So, Custom Camera Calibration – if you do it right then you’ll be profiling every body/lens combo you have, at every conceivable ISO value and lighting condition – it’s one of those things that if you don’t do it all then you’d be best off not doing at all in most cases.

I can think of a few instances where I would do it as a matter of course, such as scientific work, photo-microscopy, and artwork photography/copystand work etc, but these would be well outside the remit the more normal photographic practices.

As I said earlier, the Passport device itself is worth far more than it’s weight in gold – set up and light your shot and include the Passport device in a prominent place. Take a second shot without it and use shot 1 to custom white balance shot 2 – a dead easy process that makes the device invaluable for portrait and studio work etc.

But I hope by now you can begin to see the futility of trying to use a custom camera calibration profile on a “one size fits all” basis – it just won’t work correctly; and yet for the most part this is how it’s marketed – especially by third party retailers.

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Speed Light Photography

Posted on September 23, 2014 by Andrew Astbury

Speed Light Photography – part 1

First things first, apologies for the gap in blog entries – I’ve been a bit “in absentia” of late for one reason or another. I’ve got a few gear reviews to do between now and the end of the year, video tutorial ideas and requests are crawling out of the woodwork, and my ability to organise myself has become something of a crumbling edifice!

I blame the wife myself………………..

But I’ve come to the conclusion that for one reason or another I’ve become somewhat pigeon-holed as a wildlife/natural history photographer – going under the moniker of Wildlife in Pixels it’s hardly a big surprise is it..

But I cut my photographic teeth on studio product/pack shot and still life work – I loved it then and I still do. And there’s NOTHING that teaches you more about light than studio work – it pays dividends in all aspects of photography, wildlife and landscape work are no exception. Understanding how light behaves, when it’ll look good and when it’ll look like a bag of spanners is what helps capture mood and atmosphere in a shot.

The interaction between light and subject is what makes a great image, and I do wish photographers would understand this – sadly most don’t.

To this end I’ve begun to teach workshops that try to give those attending a flavor of the basic concepts of light by introducing them to the idea of using their speed lights to produce images they can do 365 days a year cum rain or shine – high speed flash, and simple product still life.

Both styles demand a high level of attention to detail in the way the light produced by the speed lights bends and wraps around the subject. Full-blown studio lights have the benefit of modelling lights so that you can see this before you take the shot, but using speed lights means you have to imagine what the light is doing, so it’s level of difficulty begins high, but decreases with practical experience.

A basic 3 light setup with speed lights can produce some really soft and moody lighting with ease.

A basic 4 light setup with speed lights can produce some really soft and moody lighting with ease.

This Black Label shot went a bit bonkers in the final stages with the addition of smoke, but it gives you an idea of the subtlety of lighting that can be achieved with speed lights.

As for the setup, here’s a shot before I introduced the glass….

Simple setup for the Black Label shot – note the well-appointed studio!

…featuring that most valuable of studio photographers tools, the Voice Activated Light Stand..!

Four SB800’s in all, the one on the right is running at 1/2 power and is fitted with an Interfit Strobies softbox and is double diffused using a Calumet 42″ frame (available here) and white diffuser – this constitutes the main light.

Just look at the size of the diffused disc on the face of that 42″ frame – all that from a poxy 2″x1″ flash head in less than 16″ – epic!

The SB800 on the left, fitted with another softbox is turned down to 1/64th power, and is there solely to illuminate the label where it wraps around the left edge of the bottle, and to get a second neck highlight. Although their is light emanating from it, its greatest effect is that of “bouncing” light from the right hand source back in to the bottle.

The V.A.L.S. is fitted with a third speed light that has a diffused snoot – note the expensive diffusion material and the highly engineered attachment method – kitchen towel and rubber band! The sole purpose of this tiny soft light is to just help pull out the left side of the bottle cap from the intensely dark background towards the top of the shot.

The 4th SB800 is fitted with a 30 degree honeycomb and a “tits ‘n ass”; or TNA2 to be more correct; filter just to give a subtle warm graduation to the background.

Speaking of the background, this is a roll of high grade tracing paper – one of the most versatile materials any studio has, both as a front lit or back lit background, or as a diffusion material – just brilliant stuff, second only to Translum plastic, and a shed-load cheaper.

At the other end of the speed light photography spectrum is the most enjoyable and fascinating pastime of high speed liquid motion photography – a posh way of saying “making a mess”!

It doesn’t have to be too messy – just don’t do it on your best Axminster!

By utilising the IGBT (Isolated Gate Bipolar Transistor) circuitry given to us in speed lights we can deploy the very fast tube burn times, or flash durations, obtained at lower output power settings to our advantage.

Simple shots of water, both dyed and clear can produce some stunning captures:

Streams of water captured back lit against a white background illuminated by two speed lights.

The background for this shot (above) is an A1 sized sheet of white foam board illuminated by a pair of SB910s. The internal reflector angle is set to 35mm and the two speed lights are placed on stands about three feet from the background, just out of shot left and right, and aimed pretty much at the center of the board to facilitate a fairly even spread of light.

The power output settings for both speed lights is set to 1/16th which gives us 1/10,000th of a second flash duration.

Switching to tracing paper as a back lit background immediately puts us at a disadvantage in that it’ll cut the amount of light we see at the camera. But a back lit background always looks just that little bit better as it makes your lighting more easy to shape and control.

Doubling the speed light count behind the trace background to 4 now gives us the power in terms of guide number equal to your average studio light – but with full IGBT advantages.

Working a little closer to the background than we were with the white board/reflected light method we can very easily generate a smooth white field of 255RGB which will make our liquid splash shots really punchy:

Working about 3 feet from a translucent background illuminated by 4 SB800’s gives us a much flatter white background, especially when deploying a 150mm or 180mm macro lens.

Shot with a 180mm macro lens at ISO 260 and f16 we have bags of depth of field on this shot.

Using 4x SB800s we can dial in the correct background exposure using the flash output power and camera ISO – we want a background that’s just on the verge of “blinkies”. If we over expose too much for the background the light will wrap around the liquid edges too much, washing out the contrast and flaring – that’s something that muppet on Adorama TV doesn’t tell you!

Take a few shots holding the glass by the rim gives us a clean foot to the glass, so we can now go and make a nice composite in Photoshop:

Composite of a couple of splash shots and a couple of “clean foot” images….

Happy sodding Valentines day for next year everyone……..yuck, but it’ll sell all day bloomin’ long!

A while ago I posted an entry on this blog about doing splash shots using a method I call “long flash short shutter” HERE.

All the shots on this entry have been taken using the “short flash long shutter” method.

This latter method is the more versatile one of the two because it has a more effective “motion freezing” power; the former method being speed-limited by the 1/8000th shutter speed – and it’s more costly on batteries!

BUT………there’s always one of those isn’t there…?

Short flash long shutter utilises the maximum X-synch speed or the camera. This is the fastest speed we can use where the sensor is FULLY open, and it’s most commonly 1/250th sec.

Sussed the massive potential pitfall yet?

That’s right – AMBIENT LIGHT.

If any ambient light reaches the sensor during our 1/250th sec exposure time then WE WILL GET MOTION BLUR that will visually amount to the same sort of effect as slow synch, sharp image with under exposed blur trails.

So we need to make sure that the ambient light is low enough to render a totally black frame.

The “long flash short shutter” method works well in conditions of high ambient provided that the action can be frozen in 1/8000th sec. If your camera only does 1/4000th sec then the method becomes somewhat less useful.

Freezing action depends on a number of things:

1. Is the subject falling under gravity or rising against it?
2. How far away is the subject?

A body falling under gravity is doing around 10mph after it’s fallen 2 feet from a dead start, and a car doing 100mph looks a lot slower when it’s 200 yards down the road than it does when it’s 20 yards away.

Similarly, if we have a cascade of liquid falling under gravity through the frame of our camera and (to avoid the jug or pouring vessel) the liquid has fallen 6 inches when it enters the top of the frame, and 30 inches when it vacates the bottom of the frame; we have to take a few things into consideration.

The liquid is faster at the bottom of the frame than at the top – think Angel Falls – the water pulls itself apart (that’s why the images can look so amazing).
If we shoot close with a short lens the speed differential across the frame will be the same BUT the overall speed will be a little more apparent than if we shoot with a longer lens from further away.

An SB910 has a 1/16th power output duration of 1/10000th sec and an SB800 1/10,900th at the same output setting (OEM-quoted values). With a 70mm lens close up this can make a subtle difference in image sharpness, but fit a 180mm and move further away from the subject to maintain composition, and the difference is non-existent.

If you are throwing liquid upwards against gravity, then it’s slowing down, and will eventually stop before falling back under the effects of gravity – quite often, 1/8000th is sufficient to freeze this sort of motion.

Both “long shutter short flash” and “short shutter long flash” are valid methods, each with their own pluses and minuses; but the method I always recommend people start with is the former “long shutter” method – it’s easier!

When a shot features a glass remember one thing – drinking glasses were invented by a race of photographer-hating beings! Glasses transmit, reflect and refract light through a full 360 degrees and you can really end up chasing your tail trying to find the source of an errant reflection if you don’t go about lighting it in the correct manner.

And if you put liquid in it then things can get a whole lot worse!

I’ll be doing some very specific workshops with Calumet in the near future that will be all about lighting glass and metal, gloss and matte surfaces, so keep your eye open if this sort of thing interests you – IT SHOULD ‘cos it’ll make you a better photographer….!

The simplest “proper” glass lighting method is what we call “bright field illumination” and guess what – that’s the method used in all the above liquid shots.

Glass Photography – Bright Field & Dark Field illumination.

In the image above, I’ve photographed the same glass using the two ancient and venerable methods of glass photography – one is easy, the other a total pain in the ass; guess which is which!

I’m not going to go into this in detail here, that’ll be in a later post; but BRIGHT FIELD defines the outline of the glass with DARK lines, and DARK FIELD defines the glass white lines of WHITE or highlight.

If you guessed DARK FIELD is the pain the bum then you were right – you will see bits of your “studio” reflected in the glass you didn’t even know existed unless you get this absolutely spot on and 100% correct.

The nice thing about studio-style photography is that you have thinking time, without pressure from working with people, animals or weather and a constantly moving sun. You can start to work up a shot and then leave it over night, when you come back the next day and click the shutter everything is as you left it – unless you’ve had burglars.

You do develop a habit of needing more “grips” gear – you’ve NEVER got the right bit! But then again it’s far cheaper than the bad habit of tripod accumulation like my friend Malc is afflicted with!

Later Folks!

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The ND Filter

Posted on July 16, 2014 by Andrew Astbury

Long Exposure & ND Filters

long exposure,slow shutter speed,ND filter,CMOS sensor,noise

A view of the stunning rock formations at Porth Y Post on the Welsh island of Anglesey. The image is a long exposure of very rough sea, giving the impression of smoke and fog. 30 seconds @f13 ISO 100. B&W 10stop ND – unfiltered exposure would have been 1/30th.

The reason for this particular post began last week when I was “cruising” a forum on a PoD site I’m a member of, and I came across a thread started by someone about heavy ND filters and very long exposures.

Then, a couple of days later a Facebook conversation cropped up where someone I know rather well seemed to be losing the plot over things totally by purchasing a 16 stop ND.

The poor bugger got a right mauling from “yours truly” for the simple reason that he doesn’t understand the SCIENCE behind the art of photography. This is what pisses me off about digital photography – it readily provides “instant gratification” to folk who know bugger all about what they are doing with their equipment. They then spend money on “pushing the envelope” only to find their ivory tower comes tumbling down around them because they THOUGHT they knew what they were doing………..stop ranting Andy before you have a coronary!

OK, I’ll stop “ranting”, but seriously folks, it doesn’t matter if you are on a 5DMkIII or a D800E, a D4 or a 1Dx – you have to realise that your camera works within a certain set of fixed parameters; and if you wander outside these boundaries for reasons of either stupidity or ignorance, then you’ll soon be up to your ass in Alligators!

Avid readers of this blog of mine (seemingly there are a few) will know that I’ve gone to great lengths in the past to explain how sensors are limited in different ways by things such as diffraction and that certain lens/sensor combinations are said to be “diffraction limited; well here’s something new to run up your flag pole – sensors can be thought of as being “photon limited” too!

I’ll explain what I mean in a minute…..

SENSOR TYPE

Most folk who own a camera of modern design by Nikon or Canon FAIL at the first hurdle by not understanding their sensor type.

Sensors generally fall into two basic types – CCD and CMOS.

Most of us use cameras fitted with CMOS sensors, because we demand accurate fast phase detection AF AND we demand high levels of ADC/BUFFER speed. In VERY simplistic terms, CCD sensors cannot operate at the levels of speed and efficiency demanded by the general camera-buying public.

So, it’s CMOS to the rescue. But CMOS sensors are generally noisier than CCDs.

When I say “noise” I’m NOT referring to the normal under exposure luminance noise that a some of you might be thinking of. I’m talking about the “background noise” of the sensor itself – see post HERE .

Now I’m going to over simplify things for you here – I need to because there are a lot of variables to take into account.

A Sensor is an ARRAY of PHOTOSITES or PHOTODIODES
A photodiode exists to do one thing – react to being struck by PHOTONS of light by producing electrons.
To produce electrons PROPORTIONAL to the number of photons that strike it.

Now in theory, a photodiode that sees ZERO photons during the exposure should release NO ELECTRONS.

At the end of the exposure the ADC comes along and counts the electrons for each photodiode – an ANALOGUE VALUE – and converts it to a DIGITAL VALUE and stores that digital value as a point of information in the RAW file.

A RAW converter such as Lightroom then reads all these individual points of information and using its own in-built algorithms it normalises and demosaics them into an RGB image that we can see on our monitor.

Sounds simple doesn’t it, and theoretically it is. But in practice there’s a lot of places in the process where things can go sideways rapidly……..!

We make a lot of assumptions about our pride and joy – our newly purchased DSLR – and most of these assumptions are just plain wrong. One that most folk get wrong is presuming ALL the photodiodes on their shiny new sensor BEHAVE IN THE SAME WAY and are 100% identical in response. WRONG – even though, in theory, it should be true.

Some sensors are built to a budget, some to a standard of quality and bugger the budget.

Think of the above statement as a scale running left to right with crap sensors like a 7D or D5000 on the left, and the staggering Phase IQ260 on the right. There isn’t, despite what sales bumph says, any 35mm format sensor that can come even close to residing on the right hand end of the scale, but perhaps a D800E might sit somewhere between 65 and 70%.

The thing I’m trying to get at here is that “quality control” and “budget” are opposites in the manufacturing process, and that linearity and uniformity of photodiode performance costs MONEY – and lots of it.

All our 35mm format sensors suffer from a lack of that expensive quality control in some form or other, but what manufacturers try to do is place the resulting poor performance “outside the envelope of normal expected operation” as a Nikon technician once told me.

In other words, during normal exposures and camera usage (is there such a thing?) the errors don’t show themselves – so you are oblivious to them. But move outside of that “envelope of normal expected operation” and as I said before, the Alligators are soon chomping on your butt cheeks.

REALITY

Long exposures in low light levels – those longer than 30 to 90 seconds – present us with one of those “outside the envelope” situations that can highlight some major discrepancies in individual photodiode performance and sensor uniformity.

Earlier, I said that a photodiode, in a perfect world, would always react proportionally to the number of photons striking it, and that if it had no photon strikes during the exposure then it would have ZERO output in terms of electrons produced.

Think of the “perfect” photodiode/photosite as being a child brought up by nuns, well mannered and perfectly behaved.

Then think of a child brought up in the Gallagher household a la “Shameless” – zero patience, no sense of right or wrong, rebellious and down right misbehaved. We can compare this kid with some of the photodiodes on our sensor.

These odd photodiodes usually show a random distribution across the sensor surface, but you only ever see evidence of their existence when you shoot in the dark, or when executing very long exposures from behind a heavy ND filter.

These “naughty” photodiodes behave badly in numerous ways:

They can release a larger number of electrons than is proportional to their photon count.
They can go to the extreme of releasing electrons when the have a ZERO photon count.
They can mimic the output of their nearest neighbors.
They can be clustered together and produce random spurious specks of colour.

And the list goes on!

It’s a Question of Time

These errant little buggers basically misbehave because the combination of low photon count and overly long exposure time allow them to, if you like, run out of patience and start misbehaving.

It is quite common for a single photodiode or cluster of them to behave in a perfect manner for any shutter speed up to between 30 seconds and 2 minutes. But if we expose that same photodiode or cluster for 3 minutes it can show abnormal behavior in its electron output. Expose it for 5 minutes and its output could be the same, or amplified, or even totally different.

IMPORTANT – do not confuse these with so-called “hot pixels” which show up in all exposures irrespective of shutter duration.

Putting an ND filter in front of your lens is the same as shooting under less light. Its effect is even-handed across all exposure values in the scenes brightness range, and therein lies the problem. Cutting 10 stops worth of photons from the highlights in the scene will still leave plenty to make the sensor work effectively in those areas of the image.

But cutting 10 stops worth of photons from the shadow areas – where there was perhaps 12 stops less to begin with – might well leave an insufficient number of photons in the very darkest areas to make those particular photodiodes function correctly.

Exposure is basically a function of Intensity and Time, back in my college days we used to say that Ex = I x T !

Our ND filter CUTS intensity across the board, so Time has to increase to avoid under exposure in general. But because we are working with far fewer photons as a whole, we have to curb the length of the Time component BECAUSE OF the level of intensity reduction – we become caught in a “Catch 22” situation, trying to avoid the “time triggered” malfunction of those errant diodes.

Below is an 4 minute exposure from behind a Lee Big Stopper on a 1Dx – click on both images to open at full resolution in a new window.

Canon 1Dx
4 minutes @ f13
ISO 200 Lee 10stop

The beastly Nikon D800E fairs a lot better under similar exposure parameters, but there are still a lot of repairs to be done:

A 4 minute exposure on a D800, f11 at 200ISO

Most people use heavy ND filters for the same reason I do – smoothing out water.

The texture of the water in the top shot clutters the image and adds nothing – so get rid of it! D4,ISO 50, 30secs f11 Lee Big Stopper

Then we change the camera orientation and get a commercial shot:

Cemlyn Bay on the northwest coast of Anglesey, North Wales, Approximately 2.5 km to the east is Wylfa nuclear power station. Same exposure as above.

In this next shot all I’m interested in is the jetty, neither water surface texture or horizon land add anything – the land is easy to dump in PShop but the water would be impossible:

I see the bottom image in my head when I look at the scene top left. Again, the 10 stop ND fixes the water, which adds precisely nothing to the image. D4 ISO 50, 60 secs, f14 B&W 10 stop

The mistake folk make is this, 30 seconds is usually enough time to get the effect on the water you want, and 90 to 120 seconds is truly the maximum you should ever really need. Any longer and you’ll get at best no more effect, and at worst the effect will not look as visually appealing – that’s my opinion anyway.

This time requirement dovetails nicely with the “operating inside the design envelope” physics of the average 35mm format sensor.

So, as I said before, we could go out on a bit of a limb and say that our sensors are all “photon limited”; all diodes on the sensor must be struck by x number of photons.

And we can regard them as being exposure length limited; all diodes on the sensor must be struck by x photons in y seconds in order to avoid the pitfalls mentioned.

So next time you have the idea of obtaining something really daft, such as the 16 stop ND filter my friend ordered, try engaging your brain. An unfiltered exposure that meters out at 1/30th sec will be 30 seconds behind a 10 stop ND filter, and a whopping 32 minutes behind a 16 stop ND filter. Now at that sort of exposure time the sensor noise in the image will be astonishing in both presence and variety!

As I posted on my Book of Face page the other day, just for kicks I shot this last Wednesday night:

Penmon Lighthouse in North Wales at twilight.
Sky is 90 secs, foreground is 4 minutes, D4, f16, ISO 50 B&W 10 stop ND filter

The image truly gives the wrong impression of reality – the wind was cold and gusting to 30mph, and the sea looked very lumpy and just plain ugly.

I spent at least 45 minutes just taking the bloody speckled colour read noise out of the 4 minute foreground exposure – I have to wonder if the image was truly worth the effort in processing.

When you take into account everything I’ve mentioned so far plus the following:

Long exposures are prone to ground vibration and the effects of wind on the tripod etc
Hanging around in places like the last shot above is plain dangerous, especially when it’s dark.

you must now see that keeping the exposures as short as possible is the sensible course of action, and that for doing this sort of work a 6 stop ND filter is a more sensible addition to your armoury than a 16 stop ND filter!

Just keep away from exposures above 2 minutes.

And before anyone asks, NO – you don’t shoot star trails in one frame over 4 hours unless you’re a complete numpty! And for anyone who thinks you can cancel noise by shooting a black frame think on this – the black frame has to be shot immediately after the image, and has to be the same exposure duration as the main image. That means a 4 hour single frame star trail plus black frame to go with it will take at least 8 hours – will your camera battery last that long? If it dies before the black frame is finished then you lose BOTH frames……………

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Exposure Compensation

Posted on July 13, 2014 by Andrew Astbury

Exposure Compensation

Exposure Compensation – that’s something else that cropped up once or twice for the chaps on my recent Norwegian Eagle workshop!

We had something like 420 or more dives from eagles during the trip, and very few if any were shot with flat metering, or 0Ev compensation.

What is Exposure Compensation, and why do we need to use it?

It all begins with this little button:

D3 Exposure Compensation button – Nikon, Canon and most others use the same symbol.

Pushing this button and rotating your main command dial will select a certain exposure compensation value.

Why do we need to use Exposure Compensation though?

Cameras, for all their complexity and “intelligent whotsits” are basically STUPID! They don’t know WHAT you are trying to photograph, or HOW you are trying to photograph it.

They make a lot of very basic assumptions about what you are trying to do – 99.99% of which are WRONG!

The camera does NOT know if you are trying to photograph:

A white cat in a coal shed
A black cat in a snow storm
A white cat in a snow storm
A black cat in a coal shed

All it sees is a frame full of various amounts of light and shade, and depending on your metering mode (which should always be Matrix/Evaluative – see post here) it gives you an “average mean exposure value”.

Take a general scene of fairly low contrast under flat overcast light:

A scene as WE see it.

The same scene as the camera METER sees it.

Lighter tones within the scene.

Some darker area tones within the scene.

The exposure is governed by the PREDOMINANT tone.

As discussed in the previous metering article mentioned earlier, only MATRIX/EVALUATIVE takes the entire frame area into account.

Okay, so that scene was fairly bland on the old tonal front, so let’s have a look at something a little more relevant:

Straight off the camera with no processing. 1/2000th @ f4 1600ISO +1.3Ev

As the camera metered the scene WITHOUT compensation.

Why would the image be so dark and under exposed?

Well here’s an approximation of the cameras average tone “thought process”:

The approximate average value of the scene.

But if we look at some averages WITHIN the overall image:

Random tonal averages within the image.

We can see that the tonal values for the subject are generally darker than the average scene value, therefore the camera records those values as “under exposed”.

This is further compounded by the cameras brain making the decision that the commonest tonal value MUST represent “mid grey” – which it DOESN’T; it’s lighter than that – and so under exposing the image even further!

Now I’m not going to get into the argument about “what is mid grey” and do Nikon et al calibrate to 12%, 18%, 20% or whatever – to be honest it’s “neither here nor there” from our standpoint.

What is CRITICAL though is that we understand the old adage:

“Light Subject Dark Background = Under, or negative exposure compensation. And that Dark Subject Light Background = Over, or positive exposure compensation”.

Okay, but what are we actually doing?

In any exposure mode other than Manual mode, we are allowing the camera to meter the scene AND make the decision over which shutter speed or aperture to use depending on whether we have the camera in Av or Tv mode – that’s Canon-speak for A or S on Nikon.

If we are in shutter priority/S/Tv mode then the camera sets the aperture to give us its metered exposure – that thing that’s usually WRONG! – at the shutter speed we’ve selected.

If, as in the case above, we ADD +1.3Ev – one and one third stops of POSITIVE exposure compensation, the camera uses the shutter speed we’ve selected but then opens up the aperture WIDER than it’s “brain” wants it to.

How wide? 1.3 stops wider, thus allowing 1.3 stops more light into the the sensor during the exposure time.

If we were in Av/A or aperture priority mode then it’s the shutter speed that would take up the slack and become 1.3 stops SLOWER than the cameras “brain” wanted it to be.

Here’s an example of negative exposure compensation:

1/3200th @ f4.5 1000ISO -1.3Ev exposure compensation.

In this particular shot we’re pointing towards the sun – a “dark subject, light background” positive exposure compensation scenario, or so you’d think.

But I want to “protect” those orange highlights in the water and the brightest tones in the eagle, so if I “peg those highlights” just over a stop below the top end of the cameras’ tonal response curve then there is no way on earth they are going to “blow” in the final RAW file.

Manual Exposure mode can still furnish us with exposure compensation based on metering if we engage AUTO-ISO. If we decide we want to shoot continuously with a high shutter speed and a set aperture at a fixed ISO then our exposures are going to be all over the place. But if we engage AUTO-ISO and let the camera choose the ISO speed via the meter reading, we can use the exposure compensation adjustments just the same as we do in Av or Tv modes.

This get’s us away from the problem of fixed ISO Tv mode running out of aperture in low light or when very high shutter speeds are needed; or conversely, stopping the aperture down too far when the sun comes out! – I’ll do a breakdown on this method of shooting later in the year – it’s not without it’s problems.

Next time you get the chance to stand by a large lake or other body of water, just take a moment to notice that the water is dark in some places and light in others. ambient light falling on a moving subject can easily be very uniform and so the subject basically has the same exposure value all the time. But it’s the changing brightness of the background as the subject moves across it that causes us to need exposure compensation.

People seem to think there’s some sort of “magic” at play when they come out with me and I’m throwing exposure compensation values at them. But there’s no magic here folks, just an ability to see beyond “the subject, framing etc” and to actually “see the light” and understand it.

After all, when we click our shutters we are imaging light – the subject is, for the most part, purely incidental!

And there’s only one way you can learn to see light and grasp its implications for camera exposure, and that’s to practice.

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Auto Focus Work Out

Posted on July 1, 2014 by Andrew Astbury

Auto Focus Work Out

My recent summer trip to Flatanger in Norway, and to the famous “Eagle Man of Norway” Ole Martin Dahle, proved, as ever, a severe test of the auto focus capabilities of the gear!

We had 4 guys on the trip, 3 Nikon and 1 Canon, and White-tailed Eagles doing more than 40mph and turning on a dime is one of the hardest tests for auto focus tracking and lock on that you can imagine – especially when it’s all done hand held from a boat that’s rolling around in the sea swell.

wildlife photography,auto focus,Nikon,D4,Andy Astbury,eagle,Norway,workshop,camera settings

The Guys – yours truly, Malcolm Clayton and Paul Atkins; and Mohamed El Ashkar (all the way from Cairo!) and our Cambridge “Don” – all trips should have one – Jamie Gundry. Photo by Ole Martin Dahle.

We had a conglomeration of D4’s, D800E’s and 200-400 f4’s, with a smattering of 300mm and 400mm f2.8’s – and then there was Mohamed with his solitary 1Dx and 300 f2.8.

And our target:

Say “Hello” to “Brutus” – an eagle who lives up to his name for sure – a total brute, especially to a boat full of daft photographers! CLICK for larger view.

Just to set the scene with regard to the technical side of things; birds fly into the wind given the choice, and the sun is wherever it decides to be! So the boat driver – Ole – always needs to position the boat so that “wind and sunlight” are coming from pretty much the same direction, otherwise the birds are not front-lit and cast their own shadows across themselves. In other words the images look like crap!

Some birds come towards the boat, take the fish and then turn away; some will do their approach parallel to the boat; and gits like Brutus will fly low and fast straight at you, pick the fish and then turn straight for the boat and climb.

But no matter how they choose to approach the camera boat all the birds pick the fish and go back to where they’ve come from.

Ole has intimate knowledge of these birds as individuals, and so has a damn good idea of what they will do as they come to the boat. This enables him to manoeuvre the boat for the best shots, and this skill is what you pay for.

Perhaps by now you’ve got the general feel for the situation – a boat that’s subject to wave motion and which might suddenly go backwards 10 yards through its own wake – not the steadiest of camera platforms!

Couple that with trying to make the auto focus lock on and track the bird, and maintain a modicum of composition – it’s just damned hard work.

Photographing anything that’s moving is hard work; moving erratically is even harder; and hand holding on an oscillating camera platform makes the job beyond hard. This style of shooting will NEVER yield vast rafts of sharp sequential images – anyone who tells you different is an outright liar. Christ, even licensed FIA F1 ‘togs are on “easy street” by comparison.

Auto focus cannot be set up perfectly for this sort of situation, but understanding it is a MUST if you want to maximise the opportunity.

Auto Focus Choices

There are 3 main things that control the effectiveness of auto focus and AF tracking:

AF Area Mode

AF Tracking Lock-on interval

Frame Rate

(Bare in mind I’m talking Nikon here, but sorting Mohameds’ 1Dx out showed my that Canon AF is pretty much the same).

Now I dealt with the latter in a previous post HERE and so we need to concentrate here on AF area modes in the main.

Let’s look at what we have to work with on a Nikon body – in this case a D4:

Firstly, the AF sensor layout.

All 51 focus sensors, and there approximate layout in relation to the image frame:

All 51 of the Nikon Multi Cam 3500 FX focus sensors – both cross and linear sensors depicted.

Just the Cross-type Sensors:

wildlife photography,auto focus,Nikon,D4,Andy Astbury,eagle,Norway,workshop,camera settings,Nikon Multi-Cam 3500 FX unit

The 15 Cross type focus sensors on the Nikon Multi-Cam 3500 FX unit.

The Linear-type Sensors:

The 36 Linear type focus sensors on the Nikon Multi-Cam 3500 FX unit.

Single Area AF

Single Area, or single point AF.

9 Point Dynamic Area AF:

9 Point Dynamic Area AF

9 Point DA AF as displayed in the viewfinder (drop shadows added in Photoshop behind the dots to aid visibility in this article).

21 Point Dynamic Area AF:

21 Point Dynamic Area AF

21 Point DA AF as displayed in the viewfinder (drop shadows added in Photoshop behind the dots to aid visibility in this article).

51 Point Dynamic Area AF:

51 Point DA AF as displayed in the viewfinder (drop shadows added in Photoshop behind the dots to aid visibility in this article).

As a stills photographer you are using what’s called Phase Detection auto focus (that’ll be another blog post topic!) but it still relies on a mix of contrast,luminosity and colour to work out what it should be concentrating on in the frame.

Consider the following 2 images, A & B:

A. Dark Subject and Light Background.
Subject itself is low contrast, background water is higher contrast. Subject is at 15 meters, Focal Length is 240mm

B. Light Subject against a Dark Background.
Subject now has a slightly higher contrast, and background is lower contrast. Subject 29 meters, Focal length 360mm

Auto focus is dumb; just plain stupid, left to its own devices. It, like me (yep, me dumb too!) favours lighter things with a higher degree of contrast. The lighter something is then the brighter and more saturated it colour is, and this in turn gives it higher localised contrast.

Auto focus will be happier locking on to and tracking Eagle B than Eagle A.

In A, the AF will want to switch to the lighter, more contrasty water behind the bird – unless of course you “hobble it” and stop it from doing so…

And you stop it by BLINDING IT – in other words use LESS active auto focus points!

“If it ain’t got ’em it can’t switch to ’em!”

If all the AF points in use are on the important part of the subject (the EYE in this case) then there’s little or no chance of the auto focus switching to somewhere you don’t want it to go to.

In a perfect world we’d all be using Single Area AF on a tripod and panning away quite happily keeping that single sensor on the targets eye……………oh I wish!!!!!!

51 point AF is out for this sort of work – with what I’ve just written you should now easily understand why.

So we are down to either the 9 point or 21 point Dynamic Areas.

It all comes down to two things:

How steady you can keep the camera.
How big in the frame the birds are – in other words, subject distance.

But accuracy of auto focus will always be improved by using the least number of sensors you can get away with.

Image A. is at 240mm and a subject distance of 15 meters, and Image B. is at 360mm and a subject distance of 29 meters. Both images were shot using 21 point Dynamic Area AF, 1/2000th @ f7 and 1600ISO.

21 point AF, 15 meters and 240mm focal length.

21 point AF, 29 meters and 360mm focal length.

On the upper detail image there’s one, perhaps two of the 21 sensors that are NOT on the subject.

On the second image there are at least 9 sensors out of the 21 in the group that are NOT on the bird.

If the bird in image A. had been 29 meters away I’ll guarantee it would have been out of focus – why?

Lack of good directional light.
Poor subject contrast and illumination.
Brighter, higher contrast background.
More sensors “Off Target”.

And the auto focus hasn’t wanted to wander to the background on image B. because there’s nothing there for it to favour over the main subject.

How Dynamic Area AF Works

9 point DA auto focus uses the single AF point that you select, but activates the 8 points surrounding it. If you, or the subject, or both, move so that the single point you selected comes “off target” then one of those 8 surrounding points will “cover” the error and maintain focus lock and tracking until you get back on target.

In 9 point DA, auto focus ALL the sensors activated are “cross type” sensors, assuming you use a sensor on the vertical center line of the AF grid.

In 21 point DA, auto focus is still centered on the single sensor you select, but now the surrounding 20 are activated. But at least 6 of these sensors will be linear, not cross type sensors.

Auto Focus Senor Types – Cross and Linear (line).

This is going to be immensely paraphrased!

AF sensors need to see edge detail in order to work. A linear sensor can work more effectively when the edge it’s looking at is perpendicular to it.

The more an edge is parallel to said line sensor then the harder time it has in discerning when said edge is sharp or not.

But if we add 2 line sensors together at right angles to each other, then an edge that is parallel to one line is perpendicular to the other – so edge detection is greatly enhanced.

In an ideal scenario 9 point Dynamic Area AF, centered in the middle of the view finder and kept on the eagles head would be the ideal way to go, but with the other circumstances of:

Moving camera platform
Potential closeness of subject (sub 15 meters possible)

then 9 point DA might be a wee bit tight on both counts, and 21 point makes more sense from a tracking and shooting perspective.

But it leads to an initial problem with the auto focus acquiring the target in the first place. You have to pick these eagles up quite a way out, and if one is coming low to the water then there is possibly too much in the frame to act as a distraction to the auto focus unit itself; though this isn’t quite such an issue if the bird is high in the sky.

So my recommendation for any form of bird-in-flight photography is to start out at 9 point DA and see how you get on!

There is always the AF Tracking Lock On feature that you can deploy in order to “hobble” the AF unit from switching to subjects closer to or further away, but if I’m honest I find this the most sticky and difficult aspect of the Nikon system to get a precise handle on. It does exactly “what it says on the tin” but it’s the “when” and “how much by” bits that have me slightly guessing.

Sometimes I put it on long and it basically waits for perhaps 4 or 5 seconds before it tries to switch focus, while at other times it does so in less than half the time. Sometimes I feel it actually diminishes the effectiveness of the “predictive” side of the auto focus tracking unit.

But if I turn it off when hand holding the camera for flight shots then everything turns to crap – so I turn it back on again!

Again, my base recommendations for this are SHORT to NORMAL and see how things go.

One thing that can have a considerable impact on the way you perceive your auto focus effectiveness is how you have your AF release priority set up (CS a1).

There are 4 options:

Release
Focus+Release
Release+Focus
Focus

By default this is set to FOCUS. With the default setting, it’s theoretically impossible to take a soft shot. But in practice that’s not so simple, and I’ve taken many a soft shot when the D4 “thinks” things are sharp; though in the main, that seems to have been cured the minute we got trap focus back with the latest firmware upgrade.

Release means the camera will take shots irrespective of focus being acquired or not. I NEVER use this option.

Focus+Release means that the first frame will only be taken once focus is acquired, and subsequent frames will be taken irrespective of focus. This is one of my preferred options when everything is unstable – that first frame hopefully sets up the auto focus and AF tracking and so everything SHOULD keep the subsequent frames sharp – please note the use of the word “should”!

Both the above release priority modes do NOT slow the frame rate.

Release+Focus – works the opposite way to Focus+Release – it does slow the frame rate down giving the mirror more down-time and so the auto focus system has more time to work. This is my other preferred option, the one I use when the “action” may not be as repeatable.

Focus – This is the option I deploy when shooting from a tripod or when the action is not quite so fast-paced. Again, this option slows the frame rate.

The Back Button Auto Focus Option

I always use the back button for auto focus activation. There are plenty of arguments for doing this, but I just feel it’s darn right more efficient than having AF activation on the shutter button. Just don’t forget to turn AF/Shutter ON to OFF in the menu, otherwise you are just wasting time and effort!

Conclusion

A lot of folk feel that their auto focus is flawed; but more often it is they and their setup choices which are flawed.

There is no blanket panacea or magic bullet setting for your AF system – as with everything else you have to constantly evaluate the light around you, anticipate the shot and make the necessary changes to setup – otherwise it’s going to be a sad day.

But knowing how your gear works and how it reacts under different scenarios is the “meat and two veg” of good photography. Couple that with shot anticipation and the proper corrective measures and it’s off home for tea and medals!

But above all, remember to have a laugh – you’re a long time dead……..

“GIMME SOME, YOU MEAN BARSTARD!”

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Parallel Horizontals.

Posted on May 25, 2014 by Andrew Astbury

Quite often when shooting landscapes, or more commonly seascapes, you may run into a problem with parallel horizontals and distortion between far and near horizontal features such as in the image below.

Parallel horizontals that are not parallel – but should be!

This sort of error cannot be fully corrected in Lightroom alone; we have to send the image to Photoshop in order to make the corrections in the most efficient manner.

Here’s a video lesson on how to effectively do just that, using the simplest, easiest and quickest of methods:

You can watch the video at full size HERE – make sure you click the HD icon.

This is something which commonly happens when photographing water with a regular shaped man-made structure in the foreground and a foreshortened horizon line such as the receding opposite shore in this shot. But with a little logical thought these problems with parallel horizontals being “out of kilter” can be easily cured.

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Black Ink Type

Posted on May 9, 2014 by Andrew Astbury

Black ink type and black ink switching when moving from matte to luster and gloss papers – here’s my thoughts on this, initially triggered by Franks’ reply to my previous article HERE.

And I quote:

Another great and instructive article Andy. I have the r3000 but get slightly annoyed with the black ink changes from one to the other. Some further guidance on the use of these re paper ‘types’ would be appreciated by moi ~ please ♡

Look, he’s even put a heart in there – bless you Frank, that’s more than I’ve got out of ‘her indoors’ for years!

Now the basic school of thought over this switching of black ink type is this:

PK, or Photo Black ink type supposedly produces a smooth, highly glossy black.
MK or Matte Black ink type produces a dull, flat black.
Using a matte finish paper requires the MATTE black ink type.
Using Luster or Gloss paper requires the Photo black ink type.

The PK black ink type really only produces a HIGH GLOSS finish when chucked onto HIGH GLOSS media. Its’ got a rather less glossy and more ‘egg shell’ finish when used on a more luster finish paper. There does come a “tipping point” though where it will look a little shinier than the finish of the paper – and it’s this tipping point where theory, clever-dicks and user-guides tell you there’s a need to switch to the matte black ink type.

The Matte black ink type does exactly what point two says it does.

The third point – replace the word “requires” with the phrase “can cope with” and we’d be about right.

The forth point is absolutely true; get this wrong by printing with the MK black ink type on high gloss paper and you’ll just waste consumables and potentially end up with the type of clean up operation normally the preserve of Exon & BP. Dot gain on steroids!

There’s also an argument that the MK black ink type produces a deeper black on matte finish paper than the PK black ink type – this is also true:

Permajet canned profiles for Museum paper on the Epson 4800 printer using PK and MK black ink types.

As we can clearly see, the Matte black ink type does indeed accommodate a deeper black point than its counterpart Photo black ink type.

Adopting the Common Sense Approach

There are a few things we need to think about here, and the first one is my constant mantra that the choice of paper is governed by the “overall look, feel and atmosphere of the finished image” when it’s sitting there on your monitor.

Paper choice IS the final part of the creative process; for all the reasons I’ve mentioned in past blog posts.

You will also know by now that in my world there is little room for high gloss paper – it’s a total pain the bum because of its highly reflective surface; but that same surface can allow you to print the very finest of details.

But here’s common sense point number 1 – the majority of people reading this blog, attending my workshops and coming to me for 1to1 tuition CAN NOT produce images with detail fine enough to warrant this single benefit of high gloss paper.

That’s not because they’re daft or rubbish at processing either – it’s simply due to the fact that they shoot 35mm format dSLR, not £30K medium format. The sensors we commonly use can’t record enough ultra fine detail. There’s a really good comparison between the Nikon D800 and an IQ160 here, it’s well worth having a look – then you’ll see what I’m on about.

The point I’m trying to make is this; print on gloss from 35mm if you like; but you are saddling yourself with its problems but not truthfully getting any of the benefit – but you can kid yourself if you like!

I Lust After Luster Papers But How Lusty Is That Luster?

As I mentioned in the previous post, Calumet Brilliant Museum Satin Matte Natural is NOT a matte finish paper.

True matte papers never really hold much appeal for me if I’m honest, because they are very dull, flat and relatively lifeless. Yes, a 12×12 inch monochromatic image might look stunning, especially hanging in an area where reflections might prove difficult for any other print surface.

But that same image printed 8 foot square might well “kill’ any room you hang it in, just because it’s so dull and so damned BIG.

True matte papers do have their uses that’s for sure, but in the main you need to discriminate between matte and what I call matte “effect”.

Permajet Fine Art Museum 310, Matte Plus and Portrait 300 are papers that spring to mind as falling into this matte effect category – and wouldn’t you know it, there are canned profiles for these papers for both PK and MK black ink type ink sets, as you can see from the image earlier in the post.

So, with regard to black ink type switching you have to ask yourself:

Am I using a paper the ACTUALLY NEEDS the MK black ink type? Chances are you’re probably not!
If I am, do I really want to – how big a print am I doing?

In my own print portfolio I only have two images that benefit from being printed on a “dead” media surface, and they are both printed to Permajet Museum using the PK black ink type.

I had another one that looked “nearly there” but the heavy texture of the paper detracted from the image, so it was re-proofed and printed to Matt Plus, again using PK ink. It looked just the same from a colour/luminance stand point, but worse from a ‘style’ point because of the zero texture.

Along comes Calumet Museum Satin Matte Natural!

The subtle texture gets me where I wanted to be on that score, and that ever-so-soft luster just makes the colours come to life that tiny bit more, giving me a print variation that I love and hadn’t even envisaged at the time I did the original print.

Ink Type Switching

I have to say at the outset that I do NOT own an R3000 printer – I use wide format Epson printers and so have no commercial need for the 3000 DT format. But I always advise people looking for a printer to buy one – it’s a stunning machine that punches well above it’s weight based on price point.

My Epson wide format does not hold both black ink types. Switching entails a rather tedious and highly wasteful process; which I have neither desire or need to embark upon.

But if you have any brand of printer that carries both types on board then I’d highly recommend you to set the black ink type to PK, and turn any auto-switching OFF – that is, set switching to manual.

Right, now the super-pessimist in me shines through!

I’m not a fan of Epson papers on the whole, and there’s a lot more choice and far better quality available from third party suppliers ranging from Photospeed to Hahnemuhle, Canson, Red River and all points in between.

Now third party suppliers in the main will tell you to use one black ink type or the other – or either, and give you the correct media settings (Brilliant – are you reading this??).

But, if you have auto switching enabled, and use Epson paper, the print head sees the paper surface and automatically switches the ink to the ‘supposed’ correct type. This switching process requires the printer to purge the black ink line and refill it with the ‘correct’ black ink type before printing commences.

Now these figures are the stats quoted from Epson:

Black ink conversion times:

Matte to Photo Black approx. 3 min. 30 sec
Photo to Matte Black approx. 2 min. sec

Ink used during conversion:

Matte to Photo Black approx. 3 ml
Photo to Matte Black approx. 1 ml

Now why the times and volumes aren’t the same in both directions is a bit of a mystery to me and doesn’t make sense. But what is killer is that the carts are only 26 (25.9)ml and around £24 each, so 6 changes of black ink type is going to burn through as good as £25 of ink – and that’s without doing any bloody printing!!!

When ever I demo this printer at a workshop I never use Epson paper, auto switching is OFF and I never get a head sensor warning to tell me to switch ink even if I load Permajet Museum – the head sensor doesn’t warn me about the fact that I’m using PK ink.

Yes the printer could be up the spout, but using a canned PK profile the resulting print would tend to indicate otherwise.

Or something slightly more dark and sinister might be happening – or rather NOT, because I’m not using OEM paper………...What was that I heard you say? Good gracious me…you might think that but I couldn’t possibly comment!

One thing to bare in mind is this. For the most part, the majority of print media will work exceptionally well with the PK black ink type – BUT NOT THE OTHER WAY AROUND – you’ve been warned. If you want to know how the captain of the Exon Valdez felt and be up to your ass in black stuff then go ahead and give it a try, but don’t send the cleaning bills to me!

I did it once years ago with an HP printer – I can still see matte black ink tide marks on the skirting board in my office……it wasn’t pretty! And it screwed the printer up totally.

Using PK on matte media will only effect the D-max and lower the overall contrast a wee bit; unless it’s a very low key image with vast areas of blackish tones in it then for the most part you’d perhaps struggle to notice it. Sometimes you might even find that the drop in contrast even works to your advantage.

But don’t forget, you might not be using a matte media at all, even though it visually looks like it and says the word matte in the paper name. If the paper manufacturer supplies a PK and an MK profile for the same paper then save yourself time and money and use the PK profile to soft-proof to AND to control the printer colour management.

Did that answer your question Frank – FRANK – can you hear me Frank??!!

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Image Sharpness

Shameless Plug Number 1.

Understanding Canon & Nikon Autofocus

for

Bird in Flight Photography

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Lumenzia for Easy Luminosity Masking..

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Testing & Evaluation

Autofocus:

Autofocus Conclusion:

A Nikon Users Final Judgement on the 1Dx + 200-400mm f4 L IS USM

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Custom Camera Calibration

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Speed Light Photography – part 1

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Long Exposure & ND Filters

SENSOR TYPE

REALITY

It’s a Question of Time

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Exposure Compensation

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Auto Focus Work Out

Auto Focus Choices

How Dynamic Area AF Works

Auto Focus Senor Types – Cross and Linear (line).

The Back Button Auto Focus Option

Conclusion

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Quite often when shooting landscapes, or more commonly seascapes, you may run into a problem with parallel horizontals and distortion between far and near horizontal features such as in the image below.

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Black ink type and black ink switching when moving from matte to luster and gloss papers – here’s my thoughts on this, initially triggered by Franks’ reply to my previous article HERE.

Adopting the Common Sense Approach

I Lust After Luster Papers But How Lusty Is That Luster?

Ink Type Switching

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