CHROMiX

Dual displays, LUT and display profile interaction, workflow

I’m confused and have a lot of questions.

Background: It used to be that an in-the-ballpark gamma was enough for me, but recently I began doing more art on my Tablet PC, and having no way of knowing what colors I was actually using got to be too much. I bought an i1 (eye-one) Display 2 and calibrated/profiled both my tablet and my external display. Windows 7 is now set up to use those profiles as defaults, and while I’m still having trouble with my graphics driver unloading my LUTs, I can work around it for now.

1.)Dual Monitors: Windows 7 allows me to specify a default ICC profile for both displays, but it seems to me that many applications are not able to switch back and forth as the application window is moved to one display or the other. It seems that allowing programs to choose “system default profile” actually results only in use of the profile of the primary display, causing colors to be displayed differently across monitors even if the LUTs make the desktops look the same. Is my understanding correct? And if so, is there a way to fix this?

2.)How does the LUT and color management in applications interact? The LUTs, I imagine, cause the displays to render color values in a certain way. If I now view a tagged image in a color managed program like Firefox or GIMP, do I still need to specify the ICC profile of the display being used? I would have thought so in order to tell the program how my display acts, but I’ve found that enabling a display profile seems to result in some color cast. Does using an LUT as well as a display profile result in a double application of the color correction? Yet disabling the LUT didn’t seem to fix everything, either.

3) How can I work with images created in non-color-managed applications? My favorite painting program, ArtRage, has a frustrating lack of color management. So now, with my LUTs loaded, my art looks almost identical across both displays and in un-managed programs. However, if I open the image with a color managed application like the Windows Live gallery, the colors will no longer match - not the original, which I expected, but not even across displays, either. Changing the display profile whenever I move the window to correspond to the display I’m actually viewing the image on does not result in identical colors. Is there some way I can process or tag my original image so that it can be displayed consistently with the same results as in my unmanaged program?

I’d really appreciate some help and clarification. Thanks!

[ETA: If this helps clarify: If I open a tagged sRGB file in Windows Live Photo Gallery (color managed), it looks nice on my primary display but too reddish on my secondary. But my graphics card seems perfectly capable of using independent settings for each display.]

  1. Dual monitors: You are correct. On a dual monitor Windows 7 setup, only the profile for the main monitor is used by the color-managed applications like Photoshop - even if you have a PS window open on the ‘other’ display. I have not heard of any way around it yet.

  2. LUTs: I’m not sure how you’re doing things here. If you have specified to the operating system which profile is to be used for which display, then that profile is automatically loaded into the LUT of the graphics card at least when the system is started up. If you view your tagged image in a color-managed program, then the image is viewed through the tagged profile, then through the monitor profile before it is presented to you to view. The LUTs in the graphics card does affect everything you see on the screen - color managed or not. The main difference with viewing through a color-managed app is that gamma (ie: 2.2 or 1.8 ) is taken out of the equation, and conversions like moving from your working space to your monitor space can happen intelligently. So there’s no double correcting going on there. Keep in mind that with Windows, something usually needs to kick the operating system into reloading the LUTs from a profile in order for you to see a change. (In other words it does not usually happen immediately once you set the new profile.) I’m not sure why you would be getting a color cast.

There’s more information on this in one of our newsletters:
http://www.colorwiki.com/wiki/Monitors_Part_One

  1. Un-managed programs: It’s certainly not impossible to have non-managed programs display the colors with reasonable accuracy. After all, your monitor calibration is going to get you a good part of the way there. Perhaps your trouble is related again to the problem you uncovered in point #1 above.

Thanks for the helpful reply! This is so frustrating. I am now resigned to the fact that the applications are only going to use the profile for the main monitor. Now I just want to be able to specify which one the main monitor is! It seems to me that even if I set the external monitor as “primary” (the one with the start menu), it’s still the profile for the built-in that’s being applied. Is that correct? And is there any way around that?