Brilliant Supreme Lustre Paper Review
(26/07/2015: Important update added at end of post re: Canon Pixma Pro 1 .icc profile from the Brilliant website).
Printing an image is the final part of the creative process, and I don’t think there are many of my peers who would disagree with me on that score.
Whenever I’m teaching printing, be it a 1to1 session or a workshop group, I invariably get asked what my recommendation for a good general purpose printing paper would be – one that would suit the widest spread of image styles and subjects.
Until quite recently that recommendation was always the same – Permajet Oyster.
It’s a wide gamut paper – it reproduces a lot of colour and hue variation – that has a high level of brightness and is really easy to soft-proof to in Lightroom. And even though it’s not absolutely colour neutral, it’s natural base tint isn’t too cool to destroy the atmosphere in a hazy orange sunset seascape.
But, after months of printing and testing I have now changed my mind – and for good reason.
Brilliant Supreme Lustre Ultimate paper from Calumet is my new recommendation for general printing, and for anyone who wants printing with the minimum of fuss and without the hassle of trying to decide what paper to choose.
Let’s look at how the two papers stack up:
Paper Weight:
Permajet Oyster 271gsm
Brilliant Supreme Lustre Ultimate 300gsm
A heavier paper is a good thing in my book; heavier means thicker, and that means a bit more structural stability; a boon when it comes to matting and mounting, and general paper handling.
Paper Tint & Base Neutrality:
Permajet Oyster: RGB 241,246,243
Brilliant Supreme Lustre Ultimate: RGB 241,245,245
The above RGB values are measured using a ColorMunki Photo in spot colour picker mode, as are the L,a,b values below.
L,a,b Luminosity Value:
Permajet Oyster: 96.1
Brilliant Supreme Lustre Ultimate: 95.8
So both papers have the same red value in their ‘paper white’, but both have elevated green and blue values, and yes, green + blue = cyan!
But the green/blue ratios are different – they are skewed in the Permajet Oyster, but 1:1 in the Brilliant paper – so where does this leave us in terms of paper proofing?
The image below is a fully processed TIFF open in Lightroom and ready for soft-proofing:
Now if we load the image into the Permajet Oyster colour space – that’s all soft proofing is by the way – we can see a number of changes, all to the detriment of the image:
The image has lost luminance, the image has become slightly cooler overall but, there is a big colour ‘skew’ in the brown, reds and oranges of both the eagle and the muted background colours.
Now look at what happens when we send the image into the Brilliant Supreme Lustre Ultimate colour space:
Yes the image has lost luminance, and there is an overall colour temperature change; but the important thing is that it’s nowhere near as skewed as it was in the Permajet Oyster soft-proofing environment.
The more uniform the the colour change the easier it is to remove!
The only adjustments I’ve needed to make to put me in the middle of the right ball park are a +6 Temp and +2 Clarity – and we are pretty much there, ready to press the big “print me now” button.
The image below just serves to show the difference between the proof adjusted and unadjusted image:
But here is the same image soft-proofed to pretty much the same level, but for Permajet Oyster paper – click the image to see it at full size, just look at the number of adjustments I’ve had to do to get basically the same effect:
Couple of things – firstly, apologies for the somewhat violent image – the wife just pointed that out to me! Secondly though, after testing various images of vastly differing colour distributions and gamuts, I consistently find I’m having to do less work in soft-proofing with the Brilliant Supreme Lustre Ultimate paper than its rival. Though I must stress that the adjustments don’t always follow the same direction for obvious reasons..
Media Settings:
These are important. For most printers the Oyster paper has a media setting recommendation on Epson printers ( someone once told me there were other makes that used bubbles – ewee, yuck) of Premium Gloss Photo Paper or PGPP. But I find that PSPP (Premium Semi Gloss Photo Paper) works best on my 4800, and I know that it’s the recommended media setting for the Epson SCP600.
See update below for Canon Pixma Pro 1 media settings and new updated .icc profile
Conclusion:
Buy a 25 sheet box A3 HERE or 50 sheet box A4 size HERE
They say time is money, so anything that saves time is a no-brainer, especially if it costs no more than its somewhat more labour-intensive alternative.
The gamut or colour spaces of the two paper ‘canned profiles’ is shown above – red plot is the Brilliant Supreme Lustre Ultimate and white is Oyster – both profiles being for the Epson 4800. Yes, the Calumet paper gamut is slightly smaller, but in real terms and with real-world images and the relative colour-metric rendering intent I’ve not noticed any short-comings whatsoever.
I have little doubt that the gamut of the paper would be expanded further with the application of a custom profile, but that’s a whole other story.
Running at around £1 per sheet of A3 it’s no more expensive than any other top quality general printing paper, and it impresses the heck out of me with relatively neutral base tint.
So easy to print to – so buy some!
I’ll be demonstrating just how well this paper works at a series of Print Workshops for Calumet later in the year, where we’ll be using the Epson SC-P600 printer, which is the replacement for the venerable R3000.
UPDATE:
Canon Pixma Pro One .ICC Profile
If anyone has tried using the Lustre profile BriLustreCanPro1.icc that was available for download on the Brilliant website, then please STOP trying to use it – it’s an abomination and whoever produced it should be shot.
I discovered just how bad it was when I was doing a print 1to1 day and the client had a PixmaPro1 printer. I spoke to Andy Johnson at Calumet and within a couple of days a new profile was sorted out and it works great.
Now that same new profile is available for download at the Brilliant website HERE – just click and download the zip file. In the file you will find the new .icc profile which goes by the name of BriLustreCanonPro1_PPPL_1.icc
I got them to add the media settings acronym in the profile name – a la Permajet – so set the paper type to Photo Paper Pro Lustre when using this paper on the Pixma Pro 1.
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Colormunki Photo Update
Colormunki Photo Update
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.
Colormunki software downloads
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:
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.
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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:
- 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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Desktop Printing 101
Understanding Desktop Printing – part 1
Desktop 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.
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:
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.
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Gamma Encoding – Under the Hood
Gamma, Gamma Encoding & Decoding
Gamma – now there’s a term I see cause so much confusion and misunderstanding.
So many people use the term without knowing what it means.
Others get gamma mixed up with contrast, which is the worst mistake anyone could ever make!
Contrast controls the spatial relationship between black and white; in other words the number of grey tones. Higher contrast spreads black into the darker mid tones and white into the upper mid tones. In other words, both the black point and white point are moved.
The only tones that are not effected by changes in image gamma are the black point and white point – that’s why getting gamma mixed up with contrast is the mark of a “complete idiot” who should be taken outside and summarily shot before they have chance to propagate this shocking level of misunderstanding!
What is Gamma?
Any device that records an image does so with a gamma value.
Any device which displays/reproduces said image does so with a gamma value.
We can think of gamma as the proportional distribution of tones recorded by, or displayed on, a particular device.
Because different devices have different gamma values problems would arise were we to display an image that has a gamma of X on a display with a gamma of Y:
Ever wondered what a RAW file would look like displayed on a monitor without any fancy colour & gamma managed software such as LR or ACR?
A raw file displayed on the back of the camera (left) and as it would look on a computer monitor calibrated to a gamma of 2.2 & without any colour & gamma management (right).
The right hand image looks so dark because it has a native gamma of 1.0 but is being displayed on a monitor with a native gamma of 2.2
RAW file Gamma
To all intents and purposes ALL RAW files have a gamma of 1.0
Camera Sensor/Linear Gamma (Gamma 1.0)
Digital camera sensors work in a linear fashion:
If we have “X” number of photons striking a sensor photosite then “Y” amount of electrons will be generated.
Double the number of photons by doubling the amount of light, then 2x “Y” electrons will be generated.
Halve the number of photons by reducing the light on the scene by 50% then 0.5x “Y” electrons will be generated.
We have two axes on the graph; the horizontal x axis represents the actual light values in the scene, and the vertical y axis represents the output or recorded tones in the image.
So, if we apply Lab L* values to our graph axes above, then 0 equates to black and 1.0 equates to white.
The “slope” of the graph is a straight line giving us an equal relationship between values for input and output.
It’s this relationship between input and output values in digital imaging that helps define GAMMA.
In our particular case here, we have a linear relationship between input and output values and so we have LINEAR GAMMA, otherwise known as gamma 1.0.
Now let’s look at a black to white graduation in gamma 1.0 in comparison to one in what’s called an encoding gamma:
Linear (top) vs Encoded Gamma
The upper gradient is basically the way our digital cameras see and record a scene.
There is an awful lot of information about highlights and yet the darker tones and ‘shadow’ areas are seemingly squashed up together on the left side of the gradient.
Human vision does not see things in the same way that a camera sensor does; we do not see linearly.
If the amount of ambient light falling on a scene suddenly doubles we will perceive the increase as an unquantifiable “it’s got brighter”; whereas our sensors response will be exactly double and very quantifiable.
Our eyes see a far more ‘perceptually even’ tonal distribution with much greater tonal separation in the darker tones and a more compressed distribution of highlights.
In other words we see a tonal distribution more like that contained in the gamma encoded gradient.
Gamma encoding can be best illustrated with another graph:
Linear Gamma vs Gamma Encoding 1/2.2 (0.4545)
Now sadly this is where things often get misunderstood, and why you need to be careful about where you get information from.
The cyan curve is NOT gamma 2.2 – we’ll get to that shortly.
Think of the graph above as the curves panel in Lightroom, ACR or Photoshop – after all, that’s exactly what it is.
Think of our dark, low contrast linear gamma image as displayed on a monitor – what would we need to do to the linear slope to improve contrast and generally brighten the image?
We’d bend the linear slope to something like the cyan curve.
The cyan curve is the encoding gamma 1/2.2.
There’s a direct numerical relationship between the two gamma curves; linear and 1/2.2. and it’s a simple power law:
- VO = VIγ where VO = output value, VI = input value and γ = gamma
Any input value (VI) on the linear gamma curve to the power of γ equals the output value of the cyan encoding curve; and γ as it works out equals 0.4545
- VI 0 = VO 0
- VI 0.25 = VO 0.532
- VI 0.50 = VO 0.729
- VI 0.75 = VO 0.878
- VI 1.0 = VO 1.0
Now isn’t that bit of maths sexy………………..yeah!
Basically the gamma encoding process remaps all the tones in the image and redistributes them in a non-linear ratio which is more familiar to our eye.
Note: the gamma of human vision is not really gamma 1/2.2 – gamma 0.4545. It would be near impossible to actually quantify gamma for our eye due to the behavior of the iris etc, but to all intents and purposes modern photographic principles regard it as being ‘similar to’..
So the story so far equates to this:
Gamma encoding redistributes tones in a non-linear manner.
But things are never quite so straight forward are they…?
Firstly, if gamma < 1 (less than 1) the encoding curve goes upwards – as does the cyan curve in the graph above.
But if gamma > 1 (greater than 1) the curve goes downwards.
A calibrated monitor has (or should have) a calibrated device gamma of 2.2:
Linear, Encoding & Monitor gamma curves.
As you can now see, the monitor device gamma of 2.2 is the opposite of the encoding gamma – after all, the latter is the reciprocal of the former.
So what happens when we apply the decoding gamma/monitor gamma of 2.2 to our gamma encoded image?
The net effect of Encode & Decode gamma – Linear.
That’s right, we end up back where we started!
Now, are you thinking:
- Don’t understand?
- We are back with our super dark image again?
Welcome to the worlds biggest Bear-Trap!
The “Learning Gamma Bear Trap”
Hands up those who are thinking this is what happens:
If your arm so much as twitched then you are not alone!
I’ll admit to being naughty and leading you to edge of the pit containing the bear trap – but I didn’t push you!
While you’ve been reading this post have you noticed the occasional random bold and underlined text?
Them’s clues folks!
The super dark images – both seascape and the rope coil – are all “GAMMA 1.0 displayed on a GAMMA 2.2 device without any management”.
That doesn’t mean a gamma 1.0 RAW file actually LOOKS like that in it’s own gamma environment!
That’s the bear trap!
Gamma 1.0 to gamma 2.2 encoding and decoding
Our RAW file actually looks quite normal in its own gamma environment (2nd from left) – but look at the histogram and how all those darker mid tones and shadows are piled up to the left.
Gamma encoding to 1/2.2 (gamma 0.4545) redistributes and remaps those all the tones and lightens the image by pushing the curve up BUT leaves the black and white points where they are. No tones have been added or taken away, the operation just redistributes what’s already there. Check out the histogram.
Then the gamma decode operation takes place and we end up with the image on the right – looks perfect and ready for processing, but notice the histogram, we keep the encoding redistribution of tones.
So, are we back where we started? No.
Luckily for us gamma encoding and decoding is all fully automatic within a colour managed work flow and RAW handlers such as Lightroom, ACR and CapOnePro etc.
Image gamma changes are required when an image is moved from one RGB colour space to another:
- ProPhoto RGB has a gamma of 1.8
- Adobe RGB 1998 has a gamma of 2.2
- sRGB has an oddball gamma that equates to an average of 2.2 but is nearly 1.8 in the deep shadow tones.
- Lightrooms working colour space is ProPhoto linear, in other words gamma 1.0
- Lightrooms viewing space is MelissaRGB which equates to Prophoto with an sRGB gamma.
Image gamma changes need to occur when images are sent to a desktop printer – the encode/decode characteristics are actually part and parcel of the printer profile information.
Gamma awareness should be exercised when it comes to monitors:
- Most plug & play monitors are set to far too high a gamma ‘out the box’ – get it calibrated properly ASAP; it’s not just about colour accuracy.
- Laptop screen gamma changes with viewing position – God they are awful!
Anyway, that just about wraps up this brief explanation of gamma; believe me it is brief and somewhat simplified – but hopefully you get the picture!
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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?
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.
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.
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 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 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!
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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:
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:
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.
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.
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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