Upon setting out to print my fine art images I was very interested in maintaining my Adobe RGB raw file colours. This requires a knowledge of colour management. I long ago studied this subject because as a working commercial photographer I was involved in shooting and preparing my images for my client’s print work and for the web. Many, if not all of them required extremely accurate colour to properly show their products in their marketing materials.
In those days all monitors (if you even had a computer – personal ones were just beginning to appear) were capable of sRGB colour display only. Much of my career was spent shooting film and at the beginning of my career my film was handed over to pre-press “service bureaus” who took over the entire process of creating four colour separations for ads, catalogues etc. As far as output to the web was concerned there was none!
Fast forward to today. My MacBook Pro has a P3 display profile built in by default. This is a much “wider” gamut display compared to sRGB, and very similar to Adobe RGB. In my previous short blog about the Apple P3 profile I go into a little background about this development (see “Next” below).
To get to the point, we now have displays with very wide gamuts and accurate colour, something which was rare and expensive “back in the day.” And now I have an ink-jet printer that lays down 12 inks and can cover almost all of the Adobe RGB colour profile and even some colours outside of it.
Enough of my personal history – I am now dealing with basically a dream come true when it comes to printing my fine art work. Here are some considerations for your own printing adventure: – because of the present capabilities of our equipment we can now consider using “Relative Colorimetric” for our rendering intent in applications like Canon Professional Print and Layout. In the past “Perceptual” rendering intent was favoured for images because of the likelihood of “out of gamut” colours. Relative Colorimetric was usually used for specialist jobs like corporate logos involving limited colours but exacting requirements for colour. Perceptual looks at the entire gamut of your image and if anything is out of gamut it automatically regenerates the colours in the image to squeeze them in to a printable printer gamut which does alter colour in the process, although not to a large extent. The advantage being an image with smooth gradations and no colour “banding.” However, the current professional grade ink-jet printers can print virtually all of Adobe RGB, and they accept 16 bit files. Relative colorimetric on the other hand captures the exact colours in the image, which is what you want! As a precaution when opting to use Relative Colorimetric you can first go under the view menu in Photoshop and choose “Gamut Warning” to see if there are out of gamut colours and where they are, which might still cause banding problems in smooth gradated areas of the image because this rendering intent clips out of gamut colours to the nearest printable colour. These areas can be carefully desaturated in Photoshop, preserving the option to print the rest of the colours in the image exactly as they are. Another thing you can do is print a small image and check for banding before committing to a big print. As I get to the soft proofing stage in Photoshop I convert to Adobe RGB from Canon’s Wide Gamut Display to get closer to my printer’s actual colour output.
A note about profiles and Raw images. The raw files we generate in a high quality camera’s sensor contain a wide gamut of colour and tone beyond Adobe RGB. The Adobe RGB option in your camera is basically just metadata accompanying the file on output, to be used if desired. The point here is there is more colour available in the raw file than Adobe RGB can describe. My workflow as I have gone into in a previous post is to use Canon software and the Canon Wide Gamut RGB profile for my initial post-processing in 16 bit files. If you are adding saturation or enhancing shadows/highlights and changing brightness levels etc. you are better off using a wide gamut profile initially.
How does an Apple P3 display profile influence all this? The answer is it will be showing your Adobe 1998 or wide gamut profile dynamically in a similar space as Adobe RGB, which will be a very close rendition for viewing. By setting up Photoshop to use an Adobe RGB workspace for post-processing the colours will remain untouched when they go to print. If however you output to Apple P3, then you will have changed Canon’s colours. Watch this when opening your TIFF or PSD 16 bit file output from Canon’s Digital Photo Professional for the first time in Photoshop, as it automatically opens in Camera Raw. There is a fairly unnoticeable link / dropdown at the centre bottom of the Camera Raw window (circled in red) which could be set to convert your Tiff or PSD file to Apple P3 by default when you click the open button (see example below).
Why would you care about outputting your file to P3? Here I may be splitting hairs but although the Adobe RGB and the Apple P3 display profiles are similar I believe I would be “leaving Canon” at this point because the Adobe RGB’s green primary is slightly more blue than the P3 green primary. So for images with a lot of blue sky I prefer to stay in Adobe RGB which I think would show Canon’s blues a little better, especially when they have areas approaching green and cyan.
That’s it for now, hope this was helpful.
