Correct way to work with color managed applications?

@Danas_Anis I’m thinking about one possible way of checking if the colors displayed by your screen are correct: if you could find either a camera calibration target or some sample pantone color patches (possibly in the pink-ish range of skin colors), then you could find out the corresponding CIELab values and create an image filled with the same uniform Lab color. At this point you should be able to compare side-by-side the printed patch and your screen to see how good they match (please somebody correct me if I’m totally wrong here!).

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You need the same illuminant for your test chart as what the screen is calibrated for, I expect, to get the colors to match.

That’s a very good point, which by the way is valid also for comparing prints to images on the display… I think pros use special lamps for that.

…and neither of my two favorite Linux image viewers - Geeqie and Gwenview - support letting the user choose the rendering intent. Which sucks. Big time.

I discovered XNView the other day, I’m not sure whether it’s OSS but it’s definitely available in Darius Duma’s “Highly Explosive” PPA for Ubuntu and derivatives. It’s also cross platform meaning it’ll work with Linux, Mac or Windows.

And, you can also set the rendering intent!

I found Geeqie, well, too geekie for me. It seemed a bit counter intuitive and GUI messy, but XNView seems very straight forward by comparison.

Check it out. Like me, I’m sure you’ll be happy you did.

I’ve been using XnView on and off for a good 10 years, and it’s fine in Windows, but XnViewMP 0.72 didn’t fit well with other Linux apps and it had some bugs which made me return to Geeqie. I thought it was dead, as the main website still links to the changelog for 0.72 from 2014, but I found via the forum that there are newer versions, currently the newest is 0.78 from 2016-02-28, so I’ll give it another shot.

I am afraid to do it right 100% is complicated and expensive… Once I get a calibration device I will see how it works and how it’s icc files work. Will compare to the prints of the print house I print at and will decide how much truth the color managed app shows vs not color managed app but calibrated screen and will do some conclusions how to more forward. By reading more about color management in some blog I found a sentence in which it is said that it is a common issue with not fully or not correctly set up color management if color managed apps shows too yellow or mud like skin tones etc. Maybe it is true and maybe it is my case cause all I do is just load my ICC profile using displayCAL, nothing more.

Good thing is that now I read a lot more about color management, once things sink in to my brain I might be successful one day to make things be right :slight_smile:

I tried XnView but Gwenview and Geegie are still my most liked image viewers. Especially after I figured out how to make Geeqie load multiple instances (Woohoo!) so I prefer its less cluttered interface ( I made it show only image with no additional tools for coping etc. it is faster and it is easy to enable and disable color management on the fly wish Gwenview had this feature…)

One thing to check (parts of) your setup is loading the BRG.icc profile I linked earlier as your are loading your current display profile and then check if your image viewer is showing “wrong” colors – red should become blue, green should become red and blue should be turned green. If that’s the case you know that loading the profile works and that the image viewer is correctly fetching the profile from the system and applying it.

Next you should reset the profile to your normal display profile (verify that images look normal again) and open an image like the color circle linked above (DON’T use the image embedded in the post, it’s broken by the forum software!). If the word “Rot” is shown in red, “Grün” in green and “Blau” in blue then your image viewer supports loading color profiles embedded in image files.

If both of these tests worked you can be confident that your setup is working. There is one thing that wasn’t tested: the graphics card’s LUT. Unfortunately I don’t have a profile with a test vcgt tag, maybe something with x=y for red and x=0 for green and blue would work, I’ll have a look if I can create such a profile and report back.

If you also want to test your image editor’s writing capabilities you should use the same BRG profile as the image profile for an exported JPEG. Then look at the image in your known good image viewer – it should look just normal. However, when looked at in an image viewer that you know doesn’t handle color management (I always use display from imagemagick) the colors should be off like in the first test.

Once you have gone through those three tests (they shouldn’t take longer than a few minutes) we migth be able to narrow down the problems with your setup.

I managed to find a few minutes to create a VCGT test profile. Loading it should make the screen turn red. It can be used to check if the system is properly setting the video card LUT when loading the system display profile.

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I spent some time testing out XnView MP 0.78. It works well and correctly uses the chosen monitor profile and the chosen rendering intent (all set manually). I do recommend it.
Pity Geeqie doesn’t support monitor profile rendering intent selection.

Here is my xnview.ini file, I suggest you use it as a starting point as I tweaked the defaults to more photographer-friendly values.
xnview.ini.txt (12.5 KB)
Rename it from xnview.ini.txt to xnview.ini
In Linux, XnView MP 0.78 stores the file in $HOME/.config/.xnviewmp/xnview.ini so put it there if you’re using the same version.
Heads up, the next version will hopefully store it in $HOME/.config/xnviewmp/xnview.ini (the xnviewmp folder should not be hidden).

The only thing you really need to do when using this file is to set your monitor color profile in Settings > General > ICC, the rest is fine.

Double-click an image, or press enter, to open it in the editor.
Middle-click it, or press F11, to open it in the full-screen viewer.
The left/right cursors move to the previous/next image.

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Well, looks like profile loading works correctly, I get exactly same results as described, with color management on, Green becomes green, blue becomes blue, when not color managed, green becomes red, blue becomes green etc. in the color circle image. And VCGT test profile makes my screen become red. That was an interesting experience.

I know this is a really old thread, but I have the same problem with the image viewers. I have a calibrated display and use the display icc profile system wide.

Example images:

The image on the left does not contain an icc profile (sRGB). This is a Olympus camera ooc (out of camera) image.
The right image does contain an icc profile (standard sRGB from OM Workspace export).
I have this same issue with Canon: As soon as I embed an icc profile, the image looks somehow dull (right), not rich in colors (left).

My questions would be: which does render the right color? The one with embeded icc profile oder the one where is no icc profile embeded?

I really like the color rendering on out of camera jpgs, but do not understand why there is a difference, if icc profile is embedded to the same jpg or not.

Cheers

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Hi @peleme welcome to the forum.

Looks like you’re using a web browser… Which one?

Firefox is the only one with working color management last I checked, and you have to enable it. Do you see the difference with a color managed image viewer like geeqie?