Colour Management
Consistency from camera to print

Getting colours to match from image capture, editing on the computer and printing can be a nightmare. I had no real problems until I added a second monitor to my system, then things went badly wrong and it took me a long while to fix it. This is a brief outline for those it might help to encourage that it can be fixed!

I had been using Aperture on a MacBook pro for some time and had excellent results viewing, editing and printing to my HP 9180 A3 printer. I wanted to take advantage of Aperture’s ability to work with a second display so decided to buy an Apple 23” Cinema display. As Apple say in their marketing materials, these displays are beautiful and working with photographs is just fantastic after using a 15” laptop display. For a start, the image is larger than an A4 sized print on screen, and close to A3 - so getting rid of dust spots, for instance, is so much easier.

I calibrated the Apple display using a ColorVision Spyder2 and ColorEyes Display Pro software. As expected this made the display look wonderful and images had a real “pop” on screen. That’s the good news. Having spent some time getting used to this setup time for a print. Yuck. Prints had now lost their sparkle, were dark and muddy. What had gone wrong? It all looks so great on screen?

After a lot of frustrating trials, recalibration of both the big screen and laptop, fiddling with printer drivers, ICC profiles and just about anything else that would adjust I decided it was time to go back to basics. So I deleted all the Aperture presets for printing and profiles, deleted the monitor profiles that I had created and started again.

I re-calibrated the laptop screen and fired up Aperture without connecting the 23” display. Printed an image - fine. So re-connected the large screen.

I started with re-calibration of both screens using ColorEyes Display Pro v1.3 software and the Spyder2 puck. This software is capable of adjusting the screen brightness so I let it do its job. For the 23” display I used the following target settings (but please read on before you use these!):

White point: D65, 140cd/m2
Gamma: 2.2
Black point: min luminance

I performed the calibration in daylight but with no direct sunlight coming into the room. Again I tried printing but got the same results as before - not quite as dramatic but still very unsatisfactory.

In retrospect the solution should have been obvious - compare the image side by side on the MacBook Pro and Cinema displays. I did eventually do this and was surprised by the difference. Simply adjusting the large screen’s brightness could just about get a screen similar to the print and laptop display - but hardly accurate and it still results in dull prints anyway!

It was clear that the Cinema display has quite different characteristics to the MacBook Pro. Again hardly surprising. I trawled the forums and eventually stumbled on a comment that the Cinema display does run somewhat brighter than other LCDs. This triggered the grey matter and required some thinking about colour theory. The solution was eventually simple - reduce the white point setting from the “hot” 140 cd/m2 to 100. I did this and immediately was able to print something much closer to the displayed image. At 100cd/m2 the print was actually too light so I have brought it back up to 110. Fixed, at last!

A Diversion

An avenue I haven’t described above was attempting to adjust the print settings within Aperture. Using the HP 9180 drivers does introduce a bit of confusion in colour management settings in the Apple printer settings menus. I would expect to set Aperture up to use the HP supplied ICC profiles for both on-screen proofing and printing. This is exactly what the Aperture print dialog allows me to do. Then the printer settings button brings up the printer specific settings - and allows adjustments for paper type, feed, etc. There’s also the colour management settings. In one pop-down menu it allows the setting “Application Managed Colours” which is exactly what I would expect. Then I would expect a setting to explicitly turn OFF printer colour management. There isn’t although this does appear for some other printers I have used. Instead there is a ColorSync setting - the only option being “Standard”. The danger with such settings is that both the application (Aperture) and the printer apply their own colour management to the print. This will ruin the print and it is important that the application manages the colour itself. I can confirm that the ColorSync setting of “Standard” does turn off printer colour management! Confusing, but now I know.

Conclusion

If there is any conclusion to be drawn from this it is that understanding colour management is imperative if you want any real chance of precisely matching the colours all the way through from capture to print. It is confusing, there is lots of advice out there and (for me) there were several bits of missing advice!

I do wholly recommend learning a bit about the theory as it will help you figure things out when they go wrong. I can thoroughly recommend a couple of resources, both of which have helped me out:

Digital Outback Print. Ewe Steinmueller’s site provides lots of advice on printing, but in particular I recommend his eBook The Art of Fine Art Printing. Again, this is not Aperture specific but it taught me so much about colour management! Update (5th September 2008): this is now available, presumably with some updates, as a "real" book from Rocky Nook. See http://www.rockynook.com/books/1-933952-00-8.html

Luminous Landscape “From Camera to Print” training videos. This is over 6 hours worth of video and provides lots of sound advice. It does not cover Aperture but the principles are exactly the same.