Monitor Calibration Update

Monitor Calibration Update

Okay, so I no longer NEED a new monitor, because I’ve got one – and my wallet is in Leighton Hospital Intensive Care Unit on the critical list..

What have you gone for Andy?  Well if you remember, in my last post I was undecided between 24″ and 27″, Eizo or BenQ.  But I was favoring the Eizo CS2420, on the grounds of cost, both in terms of monitor and calibration tool options.

But I got offered a sweet deal on a factory-fresh Eizo CS270 by John Willis at Calumet – so I got my desire for more screen real-estate fulfilled, while keeping the costs down by not having to buy a new calibrator.

%name Monitor Calibration Update

But it still hurt to pay for it!

Monitor Calibration

There are a few things to consider when it comes to monitor calibration, and they are mainly due to the physical attributes of the monitor itself.

In my previous post I did mention one of them – the most important one – the back light type.

CCFL and WCCFL – cold cathode fluorescent lamps, or LED.

CCFL & WCCFL (wide CCFL) used to be the common type of back light, but they are now less common, being replaced by LED for added colour reproduction, improved signal response time and reduced power consumption.  Wide CCFL gave a noticeably greater colour reproduction range and slightly warmer colour temperature than CCFL – and my old monitor was fitted with WCCFL back lighting, hence I used to be able to do my monitor calibration to near 98% of AdobeRGB.

CCFL back lights have one major property – that of being ‘cool’ in colour, and LEDs commonly exhibit a slightly ‘warmer’ colour temperature.

But there’s LEDs – and there’s LEDs, and some are cooler than others, some are of fixed output and others are of a variable output.

The colour temperature of the backlighting gives the monitor a ‘native white point’.

The ‘brightness’ of the backlight is really the only true variable on a standard type of LCD display, and the inter-relationship between backlight brightness and colour temperature, and the size of the monitors CLUT (colour look-up table) can have a massive effect on the total number of colours that the monitor can display.

Industry-standard documentation by folk a lot cleverer than me has for years recommended the same calibration target settings as I have alluded to in previous blog posts:

White Point: D65 or 6500K

Brightness: 120 cdm² or candelas per square meter

Gamma: 2.2

Screen Shot 2017 04 02 at 13.04.25 Monitor Calibration Update

The ubiquitous ColorMunki Photo ‘standard monitor calibration’ method setup screen.

This setup for ‘standard monitor calibration’ works extremely well, and has stood me in good stead for more years than I care to add up.

As I mentioned in my previous post, standard monitor calibration refers to a standard method of calibration, which can be thought of as ‘software calibration’, and I have done many print workshops where I have used this method to calibrate Eizo ColorEdge and NEC Spectraviews with great effect.

However, these more specialised colour management monitors have the added bonus of giving you a ‘hardware monitor calbration’ option.

To carry out a hardware monitor calibration on my new CS270 ColorEdge – or indeed any ColorEdge – we need to employ the Eizo ColorNavigator.

The start screen for ColorNavigator shows us some interesting items:

colnav1 Monitor Calibration Update

The recommended brightness value is 100 cdm² – not 120.

The recommended white point is D55 not D65.

Thank God the gamma value is the same!

Once the monitor calibration profile has been done we get a result screen of the physical profile:

colnav2 Monitor Calibration Update

Now before anyone gets their knickers in a knot over the brightness value discrepancy there’s a couple of things to bare in mind:

  1. This value is always slightly arbitrary and very much dependent on working/viewing conditions.  The working environment should be somewhere between 32 and 64 lux or cdm² ambient – think Bat Cave!  The ratio of ambient to monitor output should always remain at between 32:75/80 and 64:120/140 (ish) – in other words between 1:2 and 1:3 – see earlier post here.
  2. The difference between 100 and 120 cdm² is less than 1/4 stop in camera Ev terms – so not a lot.

What struck me as odd though was the white point setting of D55 or 5500K – that’s 1000K warmer than I’m used to. (yes- warmer – don’t let that temp slider in Lightroom cloud your thinking!).

1000k Monitor Calibration UpdateAfter all, 1000k is a noticeable variation – unlike the brightness 20cdm² shift.

Here’s the funny thing though; if I ‘software calibrate’ the CS270 using the ColorMunki software with the spectro plugged into the Mac instead of the monitor, I visually get the same result using D65/120cdm² as I do ‘hardware calibrating’ at D55 and 100cdm².

The same that is, until I look at the colour spaces of the two generated ICC profiles:

profile Monitor Calibration Update

The coloured section is the ‘software calibration’ colour space, and the wire frame the ‘hardware calibrated’ Eizo custom space – click the image to view larger in a separate window.

The hardware calibration profile is somewhat larger and has a slightly better black point performance – this will allow the viewer to SEE just that little bit more tonality in the deepest of shadows, and those perennially awkward colours that sit in the Blue, Cyan, Green region.

It’s therefore quite obvious that monitor calibration via the hardware/ColorNavigator method on Eizo monitors does buy you that extra bit of visual acuity, so if you own an Eizo ColorEdge then it is the way to go for sure.

Having said that, the differences are small-ish so it’s not really worth getting terrifically evangelical over it.

But if you have the monitor then you should have the calibrator, and if said calibrator is ‘on the list’ of those supported by ColorNavigator then it’s a bit of a JDI – just do it.

You can find the list of supported calibrators here.

Eizo and their ColorNavigator are basically making a very effective ‘mash up’ of the two ISO standards 3664 and 12646 which call for D65 and D50 white points respectively.

Why did I go CHEAP ?

Well, cheaper…..

Apart from the fact that I don’t like spending money – the stuff is so bloody hard to come by – I didn’t want the top end Eizo in either 27″ or 24″.

With the ‘top end’ ColorEdge monitors you are paying for some things that I at least, have little or no use for:

  • 3D CLUT – I’m a general sort of image maker who gets a bit ‘creative’ with my processing and printing.  If I was into graphics and accurate repro of Pantone and the like, or I specialised in archival work for the V & A say, then super-accurate colour reproduction would be critical.  The advantage of the 3D CLUT is that it allows a greater variety of SUBTLY different tones and hues to be SEEN and therefore it’s easier to VISUALLY check that they are maintained when shifting an image from one colour space to another – eg softproofing for print.  I’m a wildlife and landscape photographer – I don’t NEED that facility because I don’t work in a world that requires a stringent 100% colour accuracy.
  • Built-in Calibrator – I don’t need one ‘cos I’ve already got one!
  • Built-in Self-Correction Sensor – I don’t need one of those either!

So if your photography work is like mine, then it’s worth hunting out a ‘zero hours’ CS270 if you fancy the extra screen real-estate, and you want to spend less than if buying its replacement – the CS2730.  You won’t notice the extra 5 milliseconds slower response time, and the new CS2730 eats more power – but you do get a built-in carrying handle!

 

Monitor Brightness.

Monitor Brightness & Room Lighting Levels.

I had promised myself I was going to do a video review of my latest purchase – the Lee SW150Mk2 system and Big and Little Stopper filters I’ve just spent a Kings ransom on for my Nikon 14-24mm and D800E:

D4D3598 Edit Monitor Brightness.

PURE SEX – and I’ve bloody well paid for this! My new Lee SW150 MkII filter system for the Nikon 14-24. Just look at those flashy red anodised parts – bound to make me a better photographer!

But I think that’ll have to wait while I address a question that keeps cropping up lately.  What’s the question?

Well, that’s the tricky bit because it comes in many guises. But they all boil down to “what monitor brightness or luminance level should I calibrate to?”

Monitor brightness is as critical as monitor colour when it comes to calibration.  If you look at previous articles on this blog you’ll see that I always quote the same calibration values, those being:

White Point: D65 – that figure takes care of colour.

Gamma: 2.2 – that value covers monitor contrast.

Luminance: 120 cdm2 (candelas per square meter) – that takes care of brightness.

Simple in’it….?!

However, when you’ve been around all this photography nonsense as long as I have you can overlook the possibility that people might not see things as being quite so blindingly obvious as you do.

And one of those ‘omissions on my part’ has been to do with monitor brightness settings COMBINED with working lighting levels in ‘the digital darkroom’.  So I suppose I’d better correct that failing on my part now.

What does a Monitor Profile Do for your image processing?

A correctly calibrated monitor and its .icc profile do a really simple but very mission-critical job.

If we open a new document in Photoshop and fill it with flat 255 white we need to see that it’s white.  If we hold an ND filter in front of our eye then the image won’t look white, it’ll look grey.

If we hold a blue filter in front of our eye the image will not look white – it’ll look blue.

That white image doesn’t exist ‘inside the monitor’ – it’s on our computer!  It only gets displayed on the monitor because of the graphics output device in our machine.

So, if you like, we’re on the outside looking in; and we are looking through a window on to our white image.  The colour and brightness level in our white image are correct on the inside of the system – our computer – but the viewing window or monitor might be too bright or too dark, and/or might be exhibiting a colour tint or cast.

Unless our monitor is a totally ‘clean window’ in terms of colour neutrality, then our image colour will not be displayed correctly.

And if the monitor is not running at the correct brightness then the colours and tones in our images will appear to be either too dark or too bright.  Please note the word ‘appear’…

Let’s get a bit fancy and make a greyscale in Photoshop:

Untitled 1 Monitor Brightness.

The dots represent Lab 50 to Lab 95 – the most valuable tonal range between midtone and highlight detail.

Look at the distance between Lab 50 & Lab 95 on the three greyscales above – the biggest ‘span’ is the correctly calibrated monitor.  In both the ‘too bright & contrasty’ and the ‘too dark low contrast’ calibration, that valuable tonal range is compressed.

In reality the colours and tones in, say an unprocessed RAW file on one of our hard drives, are what they are.  But if our monitor isn’t calibrated correctly, what we ‘see’ on our monitor IS NOT REALITY.

Reality is what we need – the colours and tones in our images need to be faithfully reproduced on our monitor.

And so basically a monitor profile ensures that we see our images correctly in terms of colour and brightness; it ensures that we look at our images through a clean window that displays 100% of the luminance being sent to it – not 95% and not 120% – and that all our primary colours are being displayed with 100% fidelity.

In a nutshell, on an uncalibrated monitor, an image might look like crap, when in reality it isn’t.  The shit really starts to fly when you start making adjustments in an uncalibrated workspace – what you see becomes even further removed from reality.

“My prints come out too dark Andy – why?”

Because your monitor is too bright – CALIBRATE it!

“My pics look great on my screen, but everyone on Nature Photographers Network keeps telling me they’ve got too much contrast and they need a levels adjustment.  One guy even reprocessed one – everyone thought his version was better, but frankly it looked like crap to me – why is this happening Andy?

“Because your monitor brightness is too low but your gamma is too high – CALIBRATE it!  If you want your images to look like mine then you’ve got to do ALL the things I do, not just some of ’em – do you think I do all this shit for fun??????????……………grrrrrrr….

But there’s a potential problem;  just because your monitor is calibrated to perfection, that does NOT mean that everything will be golden from this point on

Monitor Viewing Conditions

So we’re outside taking a picture on a bright sunny day, but we can’t see the image on the back of the camera because there’s too much daylight, and we have to dive under a coat with our camera to see what’s going on.

But if we review that same image on the camera in the dark then it looks epic.

Now you have all experienced that…….

The monitor on the back of your camera has a set brightness level – if we view the screen in a high level of ambient light the image looks pale, washed out and in a general state of ultra low contrast.  Turn the ambient light down and the image on the camera screen becomes more vivid and the contrast increases.

But the image hasn’t changed, and neither has the camera monitor.

What HAS changed is your PERCEPTION of the colour and luminance values contained within the image itself.

Now come on kids – join the dots will you!

It does not matter how well your monitor is calibrated, if your monitor viewing conditions are not within specification.

Just like with your camera monitor, if there is too much ambient light in your working environment then your precisely calibrated monitor brightness and gamma will fail to give you a correct visualization or ‘perception’ of your image.

And the problems don’t end there either; coloured walls and ceilings reflect that colour onto the surface of your monitor, as does that stupid luminous green shirt you’re wearing – yes, I can see you!  And if you are processing on an iMac then THAT problem just got 10 times worse because of the glossy screen!

Nope – bead-blasting your 27 inches of Apple goodness is not the answer!

Right, now comes the serious stuff, so READ, INGEST and ACT.

ISO Standard 3664:2009 is the puppy we need to work to (sort of) – you can actually go and purchase this publication HERE should you feel inclined to dump 138 CHF on 34 pages of light bedtime reading.

There are actually two ISO standards that are relevant to us as image makers; ISO 12646:2015(draft) being the other.

12646 pertains to digital image processing where screens are to be compared to prints side by side (that does not necessarily refer to ‘desktop printer prints from your Epson 3000’).

3664:2009 applies to digital image processing where screen output is INDEPENDENT of print output.

We work to this standard (for the most part) because we want to process for the web as well as for print.

If we employ a print work flow involving modern soft-proofing and otherwise keep within the bounds of 3664 then we’re pretty much on the dance-floor.

ISO 3664 sets out one or two interesting and highly critical working parameters:

Ambient Light White Point: D50 – that means that the colour temperature of the light in your editing/working environment should be 5000Kelvin (not your monitor) – and in particular this means the light FALLING ON TO YOUR MONITOR from within your room. So room décor has to be colour neutral as well as the light source.

Ambient Light Value in your Editing Area: 32 to 64 Lux or lower.  Now this is what shocks so many of you guys – lower than 32 lux is basically processing in the dark!

Ambient Light Glare Permissible: 0 – this means NO REFLECTIONS on your monitor and NO light from windows or other light sources falling directly on the monitor.

Monitor White Point – D65 (under 3664) and D50 (under 12646) – we go with D65.

Monitor Luminance – 75 to 100 cdm2 (under 3664) and 80 to 120 cdm2 (under 12646 – here we begin to deviate from 3664.

We appear to be dealing with mixed reference units, but 1 Lux = 1 cdm2 or 1 candela per square metre.

The way Monitor Brightness or Luminance relates to ambient light levels is perhaps a little counter-intuitive for some folk.  Basically the LOWER your editing area Lux value the LOWER your Monitor Brightness or luminance needs to be.

Now comes the point in the story where common sense gets mixed with experience, and the outcome can be proved by looking at displayed images and prints; aesthetics as opposed numbers.

Like all serious photographers I process my own images on a wide-gamut monitor, and I print on a wide-gamut printer.

Wide gamut monitors display pretty much 90% to100% of the AdobeRGB1998 colour space.

What we might refer to as Standard Gamut monitors display something a little larger than the sRGB colour space, which as we know is considerably smaller than AdobeRGB1998.

StandardGamutvsWideGamut Monitor Brightness.

Left is a standard gamut/sRGB monitor and right is a typical wide gamut/AdobeRGB1998 monitor – if you can call any NEC ‘typical’!

Find all the gory details about monitors on this great resource site – TFT Central.

At workshops I process on a 27 inch non-Retina iMac – this is to all intents and purposes a ‘standard gamut’ monitor.

I calibrate my monitors with a ColorMunki Photo – which is a spectrophotometer.  Spectro’s have a tendency to be slow, and slightly problematic in the very darkest tones and exhibit something of a low contrast reaction to ‘blacks’ below around Lab 6.3 (RGB 20,20,20).

If you own a ColorMunki Display or i1Dispaly you do NOT own a spectro, you own a colorimeter!  A very different beast in the way it works, but from a colour point of view they give the same results as a spectro of the same standard – plus, for the most part, they work faster.

However, from a monitor brightness standpoint, they differ from spectros in their slightly better response to those ultra-dark tones.

So from a spectrophotometer standpoint I prefer to calibrate to ISO 12646 standard of 120cdm2 and control my room lighting to around 35-40 Lux.

Just so that you understand just how ‘nit-picking’ these standards are, the difference between 80cdm2 and 120 cdm2 is just 1/2 or 1/3rd of a stop Ev in camera exposure terms, depending on which way you look at it!

However, to put this monitor brightness standard into context, my 27 inch iMac came from Apple running at 290 cdm2 – and cranked up fully it’ll thump out 340 cdm2.

Most stand-alone monitors you buy, especially those that fall under the ‘standard gamut’ banner, will all be running at massively high monitor brightness levels and will require some severe turning down in the calibration process.

You will find that most monitor tests and reviews are done with calibration to the same figures that I have quoted – D65, 120cdm2 and Gamma 2.2 – in fact this non-standard set up has become so damn common it is now ‘standard’ – despite what the ISO chaps may think.

Using these values, printing out of Lightroom for example, becomes a breeze when using printer profiles created to the ICC v2 standard as long as you ‘soft proof’ the image in a fit and proper manner – that means CAREFULLY, take your time.  The one slight shortcoming of the set up is that side by side print/monitor comparisons may look ever so slightly out of kilter because of the D65 monitor white point – 6,500K transmitted white point as opposed to a 5,000K reflective white point.  But a shielded print-viewer should bring all that back into balance if such a thing floats your boat.

But the BIG THING you need to take away from the rather long article is the LOW LUX VALUE of you editing/working area ambient illumination.

Both the ColorMunki Photo and i1Pro2 spectrophotometers will measure your ambient light, as will the ColorMunki Display and i1 Display colorimeters, to name but a few.

But if you measure your ambient light and find the device gives you a reading of more than 50-60 lux then DO NOT ask the device to profile for your ambient light; in fact I would not recommend doing this AT ALL, here’s why.

I have a main office light that is colour corrected to 5000K and it chucks out 127 Lux at the monitor.  If I select the ‘measure and calibrate to ambient’ option on the ColorMunki Photo it eventually tells me I need a monitor brightness or luminance of 80 cdm2 – the only problem is that it gives me the same figure if I drop the ambient lux value to 100.

Now that smells a tad fishy to me……..

So my advice to anyone is to remove the variables, calibrate to 120 cdm2 and work in a very subdued ambient condition of 35 to 40 Lux. I find it easier to control my low lux working ambient light levels than bugger about with over-complex calibration.

To put a final perspective on this figure there is an interesting page on the Apollo Energytech website which quotes lux levels that comply with the law for different work environments – don’t go to B&Q or Walmart to do a spot of processing, and we’re all going to end up doing hard time at Her Madges Pleasure –  law breakers that we are!

Please consider supporting this blog.

This blog really does need your support. All the information I put on these pages I do freely, but it does involve costs in both time and money.

If you find this post useful and informative please could you help by making a small donation – it would really help me out a lot – whatever you can afford would be gratefully received.

Your donation will help offset the costs of running this blog and so help me to bring you lots more useful and informative content.

Many thanks in advance.

 

Colormunki Photo Update

Colormunki Photo Update – for OSX Yosemite

Both my MacPro and non-retina iMac used to be on Mountain Lion, or OSX 10.8, and nope, I never updated to Mavericks as I’d heard so many horror stories, and I basically couldn’t be bothered – hey, if it ain’t broke don’t fix it!

But, I wanted to install CapOne Pro on the iMac for the live-view capabilities – studio product shot lighting training being the biggest draw on that score.

So I downloaded the 60 day free trial, and whadyaknow, I can’t install it on anything lower than OSX 10.9!

Bummer thinks I – and I upgrade the iMac to OSX 10.10 – YOSEMITE.

Now I was quite impressed with the upgrade and I had no problems in the aftermath of the Yosemite installation; so after a week or so muggins here decided to do the very same upgrade to his late 2009 Mac Pro.

OHHHHHHH DEARY ME – what a pigs ear of a move that turned out to be!

Needless to say, I ended up making a Yosemite boot installer and setting up on a fresh HDD.  After re-installing all the necessary software like Lightroom and Photoshop, iShowU HD Pro and all the other crap I use, the final task arrived of sorting colour management out and profiling the monitors.

So off we trundle to X-Rite and download the Colormunki Photo software – v1.2.1.  I then proceeded to profile the 2 monitors I have attached to the Mac Pro.

Once the colour measurement stage got underway I started to think that it was all looking a little different and perhaps a bit more comprehensive than it did before.  Anyway, once the magic had been done and the profile saved I realised that I had no way of checking the new profile against the old one – t’was on the old hard drive!

So I go to the iMac and bring up the Colormunki software version number – 1.1.1 – so I tell the software to check for updates – “non available” came the reply.

Screen Shot 2014 12 05 at 13.50.17 646x900 Colormunki Photo Update

Colormunki software downloads

Screen Shot 2014 12 05 at 13.51.09 809x900 Colormunki Photo Update

Colormunki v1.2.1 for Yosemite

So I download 1.2.1, remove the 1.1.1 software and restart the iMac as per X-Rites instructions, and then install said 1.2.1 software.

Once installation was finished I profiled the iMac and found something quite remarkable!

Check out the screen grab below:

Screen Shot 2014 12 05 at 14.07.23 900x472 Colormunki Photo Update

iMac screen profile comparisons. You need to click this to open full size in a new tab.

On the left is a profile comparison done in the ColourThink 2-D grapher, and on the right one done in the iMacs own ColourSynch Utility.

In the left image the RED gamut projection is the new Colormunki v1.2.1 profile. This also corresponds to the white mesh grid in the Colour Synch image.

Now the smaller WHITE gamut projection was produced with an i1Pro 2 using the maximum number of calibration colours; this corresponds to the coloured projection in the Coloursynch window image.

The GREEN gamut projection is the supplied iMac system monitor profile – which is slightly “pants” due to its obvious smaller size.

What’s astonished me is that the Colormunki Photo with the new software v1.2.1 has produced a larger gamut for the display than the i1 Pro 2 did under Mountain Lion OSX 10.8

I’ve only done a couple of test prints via softproofing in Lightroom, but so far the new monitor profile has led to a small improvement in screen-to-print matching of the some subtle yellow-green and green-blue mixes, aswell as those yellowish browns which I often found tricky to match when printing from the iMac.

So, my advice is this, if you own a Colormunki Photo and have upgraded your iMac to Yosemite CHECK your X-Rite software version number. Checking for updates doesn’t always work, and the new 1.2.1 Mac version is well worth the trouble to install.

Please consider supporting this blog.

This blog really does need your support. All the information I put on these pages I do freely, but it does involve costs in both time and money.

If you find this post useful and informative please could you help by making a small donation – it would really help me out a lot – whatever you can afford would be gratefully received.

Your donation will help offset the costs of running this blog and so help me to bring you lots more useful and informative content.

Many thanks in advance.

 

Camera Calibration

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:

  1. 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!
  2. 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.

ISO1 900x665 Camera Calibration

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.

24 70 200 900x667 Camera Calibration

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:

24 70 3200 900x667 Camera Calibration

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………….

24 70 200vs3200 Camera Calibration

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:

500mm1000iso 900x578 Camera Calibration

Profile result of a 500mm f4 at 1000 ISO

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

24 70 1000ISO 900x578 Camera Calibration

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

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

500v24 70 1000ISO Camera Calibration

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:

500mm1000isoV24 70mm200iso Camera Calibration

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.

Please consider supporting this blog.

This blog really does need your support. All the information I put on these pages I do freely, but it does involve costs in both time and money.

If you find this post useful and informative please could you help by making a small donation – it would really help me out a lot – whatever you can afford would be gratefully received.

Your donation will help offset the costs of running this blog and so help me to bring you lots more useful and informative content.

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Brilliant Papers from Calumet

Brilliant Papers from Calumet

My thoughts on two papers from the Calumet Brilliant Papers range.

museum Brilliant Papers from Calumet

Brilliant Museum Printing Papers from Calumet

As I CONSTANTLY demonstrate to individuals and groups during workshops and 1to1 tuition days, printing is so damned easy it’s ridiculous.  Provided you get all your “ducks in a row” – and that’s not the hardest thing in the world to do, considering you’ve only got 3 bloody ducks!

How hard can it be???

Notwithstanding the necessity for an accurate monitor profile (duck number 1), the paper and its profile, or colour space if you like, form the back-bone of both “soft-proof” and the final print that spews forth from your printer – they’re ducks 2 and 3 respectively.

When getting someone on the “straight and narrow path to print righteousness” I always find it best practice to make them stick to one paper until they are super-familiar with the process, and begin to appreciate the fact that paper choice is the final step in the creative process.

I never want to confuse folk with custom profiles either – if I can get them onto a paper that comes supplied with a reliable OEM profile which includes the relevant MEDIA SETTINGS for the printer (these are crucial) then my work is done.

One paper with a very accurate OEM profile that has media settings as part of the profile name is Permajet Oyster 271.  A cracking paper for general purpose printing, it’s finish suits most images, and it’s still my go-to paper for prints of general wildlife and natural history subjects.

But it doesn’t suit everything, and landscapes, seascapes, and other styles of fine art imagery are the sorts of images that spring to mind.  It’s paper-white is a little on the cool side for starters – so printing a warm tone image to it increases your soft-proof workload for starters.

So I’m always trying different papers so that I can recommend them to my clients,  but no matter how good I find them, I’ll rarely recommend them if the supplied OEM profile is crap.  With the profiling gear I use I could get a workable custom profile for toilet paper if I had to, but telling someone new to printing that they need to:

  • Spend £1500 on the gear
  • Learn how to use what looks like the most scary software GUI on the planet
  • Waste 1 or 2 sheets of paper and ink printing the test charts (it’s not a waste really but that’s how they’d see it).

isn’t a real option.

But now I’m in love with two papers from Calumet and their Brilliant Papers Museum range.  They are:

  • Brilliant Papers Museum Satin Matte Natural
  • 1 Brilliant Papers from Calumet

    Brilliant Papers Museum Inkjet Paper – Satin Matte Natural

  • Brilliant Papers Museum Silver Gloss Natural
  • 2 Brilliant Papers from Calumet

    Brilliant Papers Museum Inkjet Paper – SilverGloss Natural

 

Both these papers, in my opinion, are up there with the very best of them.  And, while they cost – size for size – twice as much as something like Permajet Oyster; they are both far more than twice as beneficial to the easy production of fine art landscapes and other images that require a bit more from the printer paper to add the final touch.

I’ve used both papers on the Epson R3000 with the Epson ink set, and on my Epson 4800 that carries a Lyson ink set, and all I can say is that I’m more than impressed, and have no trouble in recommending you give them a go.

On the Epson R3000 I used the “canned profiles” downloadable from Brilliant Papers website HERE  but you need to understand that Brilliant have not exactly been sensible here and have omitted to give you any indication of correct media settings.

I’ve actually been using media settings of WCRW (water colour radiant white) for the Satin Matte Natural on the R3000 and TFAP (textured fine art paper) on the 4800.

For the Silver Gloss Natural the media settings for both printers have been UPPPL (ultra premium photo paper lustre) and results have been superb.

Just in case you don’t understand why media settings need to be set correctly, different papers require, amongst other things, different inking levels from the print head – too much ink and the print will look dark, too little and it’ll look pale and washed out.  There is also the little matter of what’s called “dot gain”.  Some papers have a hard glossy surface, others a more rough and porous one. A nozzle droplet of a particular size might be fine on a gloss paper, but that same size droplet on a fine art rag paper might well ‘bleed’ and spread out like it was on blotting paper.  This bleeding, or dot gain, leads to a reduction in sharpness of fine detail.

So, media settings are important – they ain’t there for the hell of it you know!

The “canned” profiles plot for the Epson R3000 using MK ink for Satin Matte Natural and PK ink for the Silver Gloss Natural (sRGB included for comparison):

Epson R3000 900x800 Brilliant Papers from Calumet

Click to enlarge

And for the 4800:

Epson 4800 900x800 Brilliant Papers from Calumet

Click to enlarge

I swapped the plot colours around by mistake – my bad!

I always used to like the look of images printed on Permajets Fine Art Museum 310, but 90% of the time I felt the texture somehow visually ‘got in the way’.

The texture of Brilliant Papers Museum Satin Matte Natural is not quite so pronounced which means I like it better!

In practical terms the colour space of the paper, though ever so slightly smaller than the Permajet Museum paper, does give you slightly deeper blacks and that tiny bit of extra shadow detail clarity.  All in all, a very good go-to paper, especially for the more monochromatic image such as:

D4R3875 Edit Edit 599x900 Brilliant Papers from Calumet

“The Portal”

The Brilliant Papers Silver Gloss Natural.  I find it difficult to actually describe the finish as “gloss” – it’s more like a very fine grained lustre to be honest.

And the difference between the two papers?  Well, the Silver Gloss just has that little extra contrast in the medium and darker midtones – it’s a bit like adding 8 or 10 points of clarity to an image inside of the Lightroom Dev module.  I’d definitely consider this a great paper for landscape and fine art imagery that contains just that little bit more in terms of colour variation and saturation:

D4R0016 Edit 21 607x900 Brilliant Papers from Calumet

“Stepping Stones to Oblivion”

All in all two very nice papers from the Brilliant Papers range that will be seeing regular use both in my own work, and in my workshops and tuition days; though not exactly budget-priced papers they’re no where near as pricey as some – plus, don’t you think your images are worth it?

And just in case you were wondering; I too was quite surprised at just how well matched the Brilliant canned profiles for the 4800 worked out on my Lyson ink set! I’ve written custom profiles for both of these papers, and there is generally so little difference between the custom and Brilliant profiles (which are really intended for the Epson ink set) that I can’t tell the difference between the prints I’ve done so far – and I’ve done a few!

Though for my own printing I’ll always use my custom icc profiles.

 

Please consider supporting this blog.

This blog really does need your support. All the information I put on these pages I do freely, but it does involve costs in both time and money.

If you find this post useful and informative please could you help by making a small donation – it would really help me out a lot – whatever you can afford would be gratefully received.

Your donation will help offset the costs of running this blog and so help me to bring you lots more useful and informative content.

Many thanks in advance.

 

Paper White – Desktop Printing 101

Paper White video

A while back I posted an article called How White is Paper White

As a follow-up to my last post on the basic properties of printing paper media I thought I’d post this video to refresh the idea of “white”.

In this video we basically look at a range of 10 Permajet papers and simply compare their tints and brightness – it’s an illustration I give at my print workshops which never fails to amaze all the attendees.

I know I keep ‘banging on’ about this but you must understand:

  • Very few paper whites are even close to being neutral.
  • No paper is WHITE in terms of luminosity – RGB 255 in 8 bit colour terms.
  • No paper can hold a true black – RGB 0 in 8 bit colour terms.

In real-world terms ALL printing paper is a TINTED GREY – some cool, some warm.

D4R8269 Edit 21 1024x674 Paper White   Desktop Printing 101

If we attempted to print the image above on a cool tinted paper then we would REDUCE or even CANCEL OUT the warm tonal effects and general ‘atmosphere’ of the image.

Conversely, print it to a warmer tinted ‘paper white’ and the atmosphere would be enhanced.

Would this enhancement be a good thing?  Well, er NO – not if we were happy with our original ‘on screen’ processing.

You need to look upon ‘paper white’ as another TOOL to help you achieve your goal of great looking photographs, with a minimum of fuss and effort on your part.

We have to ‘soft proof’ our images if we want to get a print off the printer that matches what we see on our monitor.

But we can’t soft proof until we have made a decision about what paper we are going to soft-proof to.

Choosing a paper who’s characteristics match our finished ‘on screen’ image in terms of TINT especially, will make the job of soft proofing much easier.

How, why?

Proper soft proofing requires us to make a copy of our original image (there’s most peoples first mistake – not making a copy) and then making adjustments to said copy, in a soft proof environment, so that it it renders correctly on the print – in other words it matches our original processed image.

Printing from Photoshop requires a hard copy, printing from Lightroom is different – it relies on VIRTUAL copies.

Either way, this copy and its proof adjustments are what get sent to the printer along what we call the PRINT PIPELINE.

The print pipeline has to do a lot of work:

  • It has to transpose our adjusted/soft proofed image colour values from additive RGB to print CMYK
  • It has to up sample or interpolate the image dpi instructions to the print head, depending on print output size.
  • It has to apply the correct droplet size instructions to each nozzle in the print head hundreds of times per second.
  • And it has to do a lot of other ‘stuff’ besides!!

The key component is the Printer Driver – and printer drivers are basically CRAP at carrying out all but the simplest of instructions.

In other words they don’t like hard work.

Printing to a paper white that matches our image:

  • Warm image to warm tint paper white
  • Cool image to cool paper white

will reduce to the amount of adjustments we have to make under soft proofing and therefore REDUCE the printer driver workload.

The less work the print driver has to do, the lower is the risk of things  ‘getting lost in translation‘ and if nothing gets lost then the print matches the on screen image – assuming of course that your eyes haven’t let you down at the soft proofing stage!

cool 600x387 Paper White   Desktop Printing 101

IMPORTANT – Click Image to Enlarge in new window

If we try to print this squirrel on the left to Permajet Gloss 271 (warmish image to very cool tint paper white) we can see what will happen.

We have got to make a couple of tweaks in terms on luminosity BUT we’ve also got to make a global change to the overall colour temperature of the image – this will most likely present us with a need for further  opposing colour channel adjustments between light and dark tones.

 

Warm 600x387 Paper White   Desktop Printing 101

IMPORTANT – Click Image to Enlarge in new window

Whereas the same image sent to Permajet Fibre Base Gloss Warmtone all we’ll have to do is tweak the luminosity up a tiny bit and saturation down a couple of points and basically we’ll be sorted.

So less work, and less work means less room for error in our hardware drivers; this leads to more efficient printing and reduced print production costs.

And reduced cost leads to a happy photographer!

Printing images is EASY –  as long as you get all your ducks in a row – and you’ve only got a handful of ducks to control.

Understanding print media and grasping the implications of paper white is one of those ducks………

This video is an extract from a Lightroom printing tutorial title I’m working on for release later in the year.

Please consider supporting this blog.

This blog really does need your support. All the information I put on these pages I do freely, but it does involve costs in both time and money.

If you find this post useful and informative please could you help by making a small donation – it would really help me out a lot – whatever you can afford would be gratefully received.

Your donation will help offset the costs of running this blog and so help me to bring you lots more useful and informative content.

Many thanks in advance.

 

Desktop Printing 101

Understanding Desktop Printing – part 1

 

print1 Desktop Printing 101Desktop printing is what all photographers should be doing.

Holding a finished print of your epic image is the final part of the photographic process, and should be enjoyed by everyone who owns a camera and loves their photography.

But desktop printing has a “bad rap” amongst the general hobby photography community – a process full of cost, danger, confusion and disappointment.

Yet there is no need for it to be this way.

Desktop printing is not a black art full of ‘ju-ju men’ and bear-traps  – indeed it’s exactly the opposite.

But if you refuse to take on board a few simple basics then you’ll be swinging in the wind and burning money for ever.

Now I’ve already spoken at length on the importance of monitor calibration & monitor profiling on this blog HERE and HERE so we’ll take that as a given.

But in this post I want to look at the basic material we use for printing – paper media.

Print Media

A while back I wrote a piece entitled “How White is Paper White” – it might be worth you looking at this if you’ve not already done so.

Over the course of most of my blog posts you’ll have noticed a recurring undertone of contrast needs controlling.

Contrast is all about the relationship between blacks and whites in our images, and the tonal separation between them.

This is where we, as digital photographers, can begin to run into problems.

We work on our images via a calibrated monitor, normally calibrated to a gamma of 2.2 and a D65 white point.  Modern monitors can readily display true black and true white (Lab 0 to Lab 100/RGB 0 to 255 in 8 bit terms).

Our big problem lies in the fact that you can print NEITHER of these luminosity values in any of the printer channels – the paper just will not allow it.

A papers ability to reproduce white is obviously limited to the brightness and background colour tint of the paper itself – there is no such think as ‘white’ paper.

But a papers ability to render ‘black’ is the other vitally important consideration – and it comes as a major shock to a lot of photographers.

Let’s take 3 commonly used Permajet papers as examples:

  • Permajet Gloss 271
  • Permajet Oyster 271
  • Permajet Portrait White 285

The following measurements have been made with a ColorMunki Photo & Colour Picker software.

L* values are the luminosity values in the L*ab colour space where 0 = pure black (0RGB) and 100 = pure white (255RGB)

Gloss paper:

  • Black/Dmax = 4.4 L* or 14,16,15 in 8 bit RGB terms
  • White/Dmin = 94.4 L* or 235,241,241 (paper white)

From these measurements we can see that the deepest black we can reproduce has an average 8bit RGB value of 15 – not zero.

We can also see that “paper white” has a leaning towards cyan due to the higher 241 green & blue RGB values, and this carries over to the blacks which are 6 points deficient in red.

Oyster paper:

  • Black/Dmax = 4.7 L* or 15,17,16 in 8 bit RGB terms
  • White/Dmin = 94.9 L* or 237,242,241 (paper white)

We can see that the Oyster maximum black value is slightly lighter than the Gloss paper (L* values reflect are far better accuracy than 8 bit RGB values).

We can also see that the paper has a slightly brighter white value.

Portrait White Matte paper:

  • Black/Dmax = 25.8 L* or 59,62,61 in 8 bit RGB terms
  • White/Dmin = 97.1 L* or 247,247,244 (paper white)

You can see that paper white is brighter than either Gloss or Oyster.

The paper white is also deficient in blue, but the Dmax black is deficient in red.

It’s quite common to find this skewed cool/warm split between dark tones and light tones when printing, and sometimes it can be the other way around.

And if you don’t think there’s much of a difference between 247,247,244 & 247,247,247 you’d be wrong!

The image below (though exaggerated slightly due to jpeg compression) effectively shows the difference – 247 neutral being at the bottom.

x1 Desktop Printing 101

247,247,244 (top) and 247,247,247 (below) – slightly exaggerated by jpeg compression.

See how much ‘warmer’ the top of the square is?

But the real shocker is the black or Dmax value:

Matte sRGB 900x723 Desktop Printing 101

Portrait White matte finish paper plotted against wireframe sRGB on L*ab axes.

The wireframe above is the sRGB colour space plotted on the L*ab axes; the shaded volume is the profile for Portrait White.  The sRGB profile has a maximum black density of 0RGB and so reaches the bottom of vertical L axis.

However, that 25.8 L* value of the matte finish paper has a huge ‘gap’ underneath it.

The higher the black L* value the larger is the gap.

What does this gap mean for our desktop printing output?

It’s simple – any tones in our image that are DARKER, or have a lower L* value than the Dmax of the destination media will be crushed into “paper black” – so any shadow detail will be lost.

Equally the same can be said for gaps at the top of the L* axis where “paper white” or Dmin is lower than the L* value of the brightest tones in our image – they too will get homogenized into the all-encompassing paper white!

Imagine we’ve just processed an image that makes maximum use of our monitors display gamut in terms of luminosity – it looks magnificent, and will no doubt look equally as such for any form of electronic/digital distribution.

But if we send this image straight to a printer it’ll look really disappointing, if only for the reasons mentioned above – because basically the image will NOT fit on the paper in terms of contrast and tonal distribution, let alone colour fidelity.
It’s at this point where everyone gives up the idea of desktop printing:

  • It looks like crap
  • It’s a waste of time
  • I don’t know what’s happened.
  • I don’t understand what’s gone wrong

Well, in response to the latter, now you do!

But do we have to worry about all this tech stuff ?

No, we don’t have to WORRY about it – that’s what a colour managed work flow & soft proofing is for.

But it never hurts to UNDERSTAND things, otherwise you just end up in a “monkey see monkey do” situation.

And that’s as dangerous as it can get – change just one thing and you’re in trouble!

But if you can ‘get the point’ of this post then believe me you are well on your way to understanding desktop printing and the simple processes we need to go through to ensure accurate and realistic prints every time we hit the PRINT button.

print2 Desktop Printing 101

Please consider supporting this blog.

This blog really does need your support. All the information I put on these pages I do freely, but it does involve costs in both time and money.

If you find this post useful and informative please could you help by making a small donation – it would really help me out a lot – whatever you can afford would be gratefully received.

Your donation will help offset the costs of running this blog and so help me to bring you lots more useful and informative content.

Many thanks in advance.

 

Lightroom Tutorials #2

 

Eagle 600x400 Lightroom Tutorials #2

Image Processing in Lightroom & Photoshop

 

In this Lightroom tutorial preview I take a close look at the newly evolved Clone/Heal tool and dust spot removal in Lightroom 5.

This newly improved tool is simple to use and highly effective – a vast improvement over the great tool that it was already in Lightroom 4.

 

Lightroom Tutorials  Sample Video Link below: Video will open in a new window

 

https://vimeo.com/64399887

 

This 4 disc Lightroom Tutorials DVD set is available from my website at http://wildlifeinpixels.net/dvd.html

How White is Paper White?

What is Paper White?

 

We should all know by now that, in RGB terms, BLACK is 0,0,0 and that WHITE is 255,255,255 when expressed in 8 bit colour values.

 

White can also be 32,768: 32,768: 32,768 when viewed in Photoshop as part of a 16 bit image (though those values are actually 15 bit – yet another story!).

 

Either way, WHITE is WHITE; or is it?

 

 

WIP00034947 Edit How White is Paper White?

Arctic Fox in Deep Snow ©Andy Astbury/Wildlife in Pixels

 

Take this Arctic Fox image – is anything actually white?  No, far from it! The brightest area of snow is around 238,238,238 which is neutral, but it’s not white but a very light grey.  And we won’t even discuss the “whiteness” of  the fox itself.

 

DSC6545 600x312 How White is Paper White?

Hen Pheasant in Snow ©Andy Astbury/Wildlife in Pixels

 

The Hen Pheasant above was shot very late on a winters afternoon when the sun was at a very low angle directly behind me – the colour temperature has gone through the roof and everything has taken on a very warm glow which adds to the atmosphere of the image.

 

WIP00052572 3 4 5 Edit 2 Edit 600x600 How White is Paper White?

Extremes of colour temperature – Snow Drift at Sunset ©Andy Astbury/Wildlife in Pixels

 

We can take the ‘snow at sunset’ idea even further, where the suns rays strike the snow it lights up pink, but the shadows go a deep rich aquamarine blue – what we might call a ‘crossed curves’ scenario, where shadow and lower mid tones are at a low Kelvin temperature, and upper mid tones and highlights are at a much higher Kelvin.

 

All three of these images might look a little bit ‘too much’ – but try clicking one and viewing it on a darker background without the distractions of the rest of the page – GO ON, TRY IT.

 

Showing you these three images has a couple of purposes:

Firstly, to show you that “TRUE WHITE” is something you will rarely, if ever, photograph.

Secondly, viewing the same image in a different environment changes the eyes perception of the image.

 

The secondary purpose is the most important – and it’s all to do with perception; and to put it bluntly, the pack of lies that your eyes and brain lead you to believe is the truth.

 

Only Mother Nature, wildlife and cameras tell the truth!

 

 

So Where’s All This Going Andy, and What’s it got to do with Paper White?

 

Fair question, but bare with me!

 

If we go to the camera shop and peruse a selection of printer papers or unprinted paper samplers, our eyes tell us that we are looking at blank sheets of white paper;  but ARE WE ?

 

Each individual sheet of paper appears to be white, but we see very subtle differences which we put down to paper finish.

 

But if we put a selection of, say Permajet papers together and compare them with ‘true RGB white’ we see the truth of the matter:

 

paper whites3 600x600 How White is Paper White?

Paper whites of a few Permajet papers in comparison to RGB white – all colour values are 8bit.

 

Holy Mary Mother of God!!!!!!!!!!!!!!!!

 

I’ll bet that’s come as a bit of a shocker………

 

No paper is WHITE; some papers are “warm”; and some are “cool”.

 

So, if we have a “warmish” toned image it’s going to be a lot easier to “soft proof” that image to a “warm paper” than a cool one – with the result of greater colour reproduction accuracy.

 

If we were to try and print a “cool” image on to “warm paper” then we’ve got to shift the whole colour balance of the image, in other words warm it up in order for the final print to be perceived as neutral – don’t forget, that sheet of paper looked neutral to you when you stuck it in the printer!

 

Well, that’s simple enough you might think, but you’d be very, very wrong…

 

We see colour on a print because the inks allow use to see the paper white through them, but only up to a point.  As colours and tones become darker on our print we see less “paper white” and more reflected colour from the ink surface.

 

If we shift the colour balance of the entire image – in this case warm it up – we shift the highlight areas so they match the paper white; but we also shift the shadows and darker tones.  These darker areas hide paper white so the colour shift in those areas is most definitely NOT desirable because we want them to be as perceptually neutral as the highlights.

 

What we need to do in truth is to somehow warm up the higher tonal values while at the same time keep the lowest tonal values the same, and then somehow match all the tones in between the shadows and highlights to the paper.

This is part of the process called SOFT PROOFING – but the job would be a lot easier if we chose to print on a paper whose “paper white” matched the overall image a little more closely.

 

The Other Kick in the Teeth

 

Not only are we battling the hue of paper white, or tint if you like, but we also have to take into account the luminance values of the paper – in other words just how “bright” it is.

 

Those RGB values of paper whites across a spread of Permajet papers – here they are again to save you scrolling back:

 

paper whites3 600x600 How White is Paper White?

Paper whites of a few Permajet papers in comparrison to RGB white – all colour values are 8bit.

 

not only tell us that there is a tint to the paper due to the three colour channel values being unequal, but they also tell us the brightest value we can “print” – in other words not lay any ink down!

 

Take Oyster for example; a cracking all-round general printer paper that has a very large colour gamut and is excellent value for money – Permajet deserve a medal for this paper in my opinion because it’s economical and epic!

 

Its paper white is on average 240 Red, 245 Green ,244 Blue.  If we have any detail in areas of our image that are above 240, 240, 240 then part of that detail will be lost in the print because the red channel minimum density (d-min) tops out at 240; so anything that is 241 red or higher will just not be printed and will show as 240 Red in the paper white.

 

Again, this is a problem mitigated in the soft proofing process.

 

But it’s also one of the reasons why the majority of photographers are disappointed with their prints – they look good on screen because they are being displayed with a tonal range of 0 to 255, but printed they just look dull, flat and generally awful.

 

Just another reason for adopting a Colour Managed Work Flow!

 

 

Help Me to Help You!

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Please note, I’ve not written this blog article for any other reason than to make its readers aware of the facts – no one pays me in cash or kind for any products mentioned in this article; it is written purely for information purposes; you do with this information “what you will”!

If you have any questions please feel free to drop me a line via email at tuition@wildlifeinpixels.net

 

 

Colour Space & Profiles

andyastbury cameratorpint Colour Space & Profiles

From Camera to Print
copyright 2013 Andy Astbury/Wildlife in Pixels

 

Colour space and device profiles seem to cause a certain degree of confusion for a lot of people; and a feeling of dread, panic and total fear in others!

 

The reality of colour spaces and device profiles is that they are really simple things, and that how and why we use them in a colour managed work flow is perfectly logical and easy to understand.

 

Up to a point colour spaces and device profiles are one and the same thing – they define a certain “volume” of colours from red to green to blue, and from black to white – and all the colours that lie in between those five points.

 

The colour spaces that most photographers are by now familiar with are ProPhotoRGB, AdobeRGB(1998) and sRGB – these are classed as “working colour spaces” and are standards of colour set by the International Color Consortium, or ICC; and they all have one thing in common; where red, green and blue are present in equal amounts the colour produced will be NEUTRAL.

 

The only real differences between these three working colour spaces is the “distances” between the five set points of red, green, blue, black and white.  The greater the distance between the three primary colours then the greater is the degree of graduation between them, hence the greater the number of potential colours.  In the diagram below we can see the sRGB & ProPhoto working colour spaces displayed on the same axes:

 

colour space volume 600x595 Colour Space & Profiles

The sRGB & ProPhoto colour spaces. The larger volume of ProPhoto contains more colour variety between red, green & blue than sRGB.

 

If we were to mark five different points on the surface of a partially inflated balloon,  and then inflate it some more then the points in relation to the balloons surface would NOT change: the points remain the same.  But the spatial distances between the points would change, as would the internal volume.  It’s the same with our five points of colour reference – red, green, blue, black & white – they do NOT change between colour spaces; red is red no matter what the working colour space.  But the range of potential colours between our 5 points of reference increases due to increased colour space volume.

 

So now we have dealt with the basics of the three main working colour spaces, we need to consider the volume of colour our camera sensor can capture – if you like, its colour space; but I’d rather use the word “gamut”.

 

Let’s take the Canon 5DMk3 as an example, and look at the volume, or gamut, of colour that its sensor can capture, in direct comparison with our 3 quantifiable working colour spaces:

 

colour space volume2 600x595 Colour Space & Profiles

The Canon 5DMk3 sensor gamut (black) in comparison to ProPhoto (largest), AdobeRGB1998 & sRGB (smallest) working colour spaces.

 

In a previous blog article I wrote – see here – I mentioned how to setup the colour settings in Photoshop, and this is why.  If you want to keep the greatest proportion of your camera sensors captured colour then you need to contain the image within the ProPhotoRGB working colour space.  If you don’t, and you use AdobeRGB or sRGB as Photoshops working colour space then you will loose a certain proportion of those captured colours – as I’ve heard it put before, it’s like a sex change operation – certain colours get chopped off, and once that’s happened you can’t get them back!

 

To keep things really simple just think of the 3 standard working colour spaces as buckets – the bigger the bucket, the more colour it contains; and you can’t tip the colours captured by your camera into a smaller bucket without getting spillage and making a mess on the floor!

 

As I said before, working colour spaces are neutral; but seldom does our camera ever capture a scene that contains pure neutrals.  Even though an item in the scene may well be neutral in colour, camera sensors quite often skew these colours ever so slightly; most Canon RAW files always look a teeny-weeny ever so slight bit magenta to me when I import them; but there again I’m a Nikon shooter seem to have a minute greenish tinge to them before processing.

 

Throughout our imaging work flow we have 3 stages:

1. Input (camera or scanner).

2. Working Process (Lightroom, Photoshop etc).

3. Output (printer for example).

 

And each stage has its representative type of colour space – we have input profiles, working colour spaces and output profiles.

 

So we have our camera capture gamut (colour space if you like) and we’ve opened our image in Photoshop or Lightroom in the ProPhoto working colour space – there’s NO SPILLAGE!

 

We now come to the crux of colour management; before we can do anything else we need to profile our “window onto our image” – the monitor.

 

In order to see the reality of what the camera captured we need to ensure that our monitor is in line with our WORKING COLOUR SPACE in terms of colour neutrality – not that of the camera as some people seem to think.

All 3 working colour spaces posses the same degree of colour neutrality where red, green & blue are present at the same values irrespective of physical size of the colour space.

So as long as our monitor is profiled to be:

 

1. Accurately COLOUR NEUTRAL

2. Displaying maximum brightness only in the presence true white – which you’ll hardly ever photograph, even snow isn’t white.

 

then we will see a highly workable representation of image colour neutrality and luminosity on our monitor.  Only by working this way can we actually tell if the camera has captured the image correctly in terms of colour balance and overall exposure.

And the fact that our monitor CANNOT display all the colours contained within our big ProPhoto bucket is, to all intents and purposes,  a fairly mute point; though seeing as many of them as possible is never a bad thing.

And using a monitor that does NOT display the volume of colour approximating or exceeding that of the Adobe working space can be highly detrimental for the reasons discussed in my previous post.

 

Now that we’ve covered input profiles and working colour spaces we need to move on and outline the basics of output profiles, and printer profiles in particular.

 

colour space volume3 600x472 Colour Space & Profiles

Adobe & sRGB working paces in comparison to the colours contained in the Kingfisher image and the profile for Permajet Oyster paper using the Epson 7900 printer. (CLICK image for full sized view).

 

In the image above we can see both the Adobe and sRGB working spaces and the full distribution of colours contained in the Kingfisher image which is a TIFF file in our big ProPhoto bucket of colour;  and a black trace which is the colour profile (or space if you like) for Permajet Oyster paper using Epson UltraChrome HDR ink on an Epson 7900 printer.

 

As we can see, some of the colours contained in the image fall outside the gamut of the sRGB working colour space; notably some oranges and “electric blues” which are basically colours of the subject and are most critical to keep in the print.

However, all those ProPhoto colours are capable of being reproduced on the Epson 7900 using Permajet Oyster paper because, as the black trace shows, the printer/ink/paper combination can reproduce colours that lie outside of the Adobe working colour space.

The whole purpose of that particular profile is to ensure that the print matches what we can see on the monitor both in terms of colour and brightness – in other words, what we see is what we get – WYSIWYG!

The beauty of a colour managed workflow is that it’s economical – assuming the image is processed correctly then printing via an accurate printer profile can give you a perfect printed rendition of your screen image using just a single sheet of paper – and only one sheets worth of ink.

 

colour space volume4 600x472 Colour Space & Profiles

The difference between colour profiles for the same printer paper on different printers. Epson 3000 printer profile trace in Red (CLICK image for full size view).

 

If we were to switch printers to an Epson 3000 using UltraChrome K3 ink on the very same paper, the area circled in white shows us that there are a couple of orange hue colours that are a little problematic – they lie either close to or outside the colour gamut of this printer/ink/paper combination, and so they need to be changed in order to ‘fit’, either by localised adjustment or variation of rendering intent – but that’s a story for later!

 

Why is it different? Well, it’s not to do with the paper for sure, so it’s down to either the ink change or printer head.  Using the same K3 ink in an Epson 4800 brings the colours back into gamut, so the difference is in the printer head itself, or the printer driver, but as I said, it’s a small problem easily fixed.

 

When you consider the low cost of achieving an accurate monitor profile – see this previous post – and combine that with an accurate printer output profile or two to match your chosen printer papers, and then deploy these assets correctly you have a proper colour managed workflow.  Add to that the cost savings in ink and paper and it becomes a bit of a “no-brainer” doesn’t it?

 

In this post I set out to hopefully ‘demystify’ colour spaces and profiles in terms of what they are and how they are used – I hope I’ve succeeded!

 

 

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