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Hello.
I have 3 different ambient light values that I want to make calibration\profile files with (Morning, noon, and night light levels)…Can I take an existing calibration\profile file and change the ambient light setting to create a new file? … (Without having to calibrate\profile all over again.)
I want to end up with three separate .icc files , each containing it’s own ambient light setting, calibration and profile…. All obtained by recalculating an existing single calibration\profile file
If I can do this, will the resulting file be just as accurate as doing it from the beginning, or am I better off starting over?
Would you please tell me how to do this. (Settings).
Thanks
Can I take an existing calibration\profile file and change the ambient light setting to create a new file? … (Without having to calibrate\profile all over again.
As long as you don’t change any controls on the monitor, and the aim is to create 3D LUTs, probably yes. It usually comes down to changing the 3D LUT gamma value (lower gamma for brighter ambient).
I’m working in 1D LUTS, can I do this?
Not without re-calibrating I’m afraid. It would help me a bit if I knew what your goal was, i.e. why you need different ambient light settings, and which software you intend to use.
I am using DisplayCAL to produce 3 separate .icc files, each calibrated to diifferent roof-light levels using your ‘ambient light’ measuring tool.
That way I’ll have 3 profiles for morning, afternoon, and night lighting conditions. (So detail in the shadows and contrast will appear consistent throughout the day and night.)
It depends on wether you’re going to use ICC color managed applications like Photoshop and wether or not you need a similar ambient light adjustment for non-color managed applications as well. For the latter, you can use the calibration ambient light level setting. For the former, this won’t suffice, and you need to create a profile incorporating CIECAM02 gamut mapping.
OMG! Really!! … Could you please tell me what to do differently then as my main concern is in color-managed applications…I was under the impression the the ambient light tool effected the calibration globally and so would alter the appearance of everything passing through thr video card gamma table.
How do I create an .icc profile\calibration containing this ‘CIECAM02 gamut mapping’ thing? … Any considerations compared to what I’m doing now?
Appreciate your help so very much Florian.
Could you please tell me what to do differently then as my main concern is in color-managed applications
In that case, all you need to do is re-generate the profile (no new measurements required) with different settings. Enable advanced options in the “Options” menu, then on the profiling tab, open gamut mapping options (the “cog” icon). Enable gamut mapping for perceptual intent and set it to “luminance matched appearance”, source viewing conditions to “monitor in typical work environment”, and alter destination viewing condition according to your ambient light (i.e. monitor in darkened/typical/bright environment). Then, select “Create profile from measurement data…” in the options menu, select your existing profile, and save to a new name. Note that you need to use perceptual intent in your applications to get the desired effect (e.g. in Photoshop, do a custom soft proof with the simulation profile set to your newly created display profile and rendering intent set to perceptual).
I was under the impression the the ambient light tool effected the calibration globally and so would alter the appearance of everything passing through thr video card gamma table.
Yes, but in color managed applications normally the source profile determines the reproduced tone curve, so that overrides the calibration.
Thank you very much Florian… I’ll have to study your instructions carefully because there are some things in them that I don’t understand yet.
I normally use Photoshop and a basic color managed image viewer called ‘Honeyview’ that allows using the monitor profile and or the .icc file of the image.
Not sure yet what this all means or if it is even appropriate in my case, but I’ll enjoy trying to figure it out.
OK, so I followed your instructions above exactly. You explained it very well! … Images are now being presented with ‘true’ blacks, FINALLY!! …Wow! so beautiful I can hardly believe what I’m seeing. Shadow detail is excellent too. I almost started to cry. Seriously, I’ve been doing soo much trial and error that I am exhausted! Thank you…
I have to be honest though. I really have no idea what I just did, lol. I’m still learning and your last instructions to me were waaaaay over my head… But still I got the result I was looking for! … I am truly grateful.
So now I have to ask:
As you know, I want to make two more of these magic .icc files (one for mid-bright room and another for very -bright room). I want to take two more room light measurements using DisplayCAL again. Do I need to start over and do two more a calibration\profile combos from scratch for both?
Do I need to change that setting to ‘normal monitor’ for one, and to ‘bright monitor’ for the other? … In other words, how would your instructions differ now that I will be starting from scratch this time. (ie. not working off an existing .icc profile to create teo more .icc profiles?
One more set of instructions and I’ll leave you alone, I promise!
Steve.
Oops, forgot to ask… What can I do to make non-color managed apps and Windows look better in my new situation? … Can I combine the best of both worlds, or is it an either\or situation?
OK, the more I study this, the more I’m beginning to see what’s going on… So, you’re saying that in color managed applications (applications which use the monitor’s profile) Won’t use the gamma curve created in the normal way. That they tend to use the source profile for gamma… So if I want to make room-light adjustment changes to the gamma curve used by color managed applications, I need to recalculate a new gamma curve in the gamut mapping options to create a gamma curve that it can use. And it is here, in the gamma mapping options that I have a choice to create a curve for different room-light conditions (High, med, low).
It seems like these choices (high, med, low) are a bit arbitrary… Why can’t the user input exact lighting conditions figures in Lux here? like he does in the room-light measuring tool? (Or are those inputs that I already put there in the origional .icc creation already being considered during the gamut conversion?)
And what about getting the same results in non-color managed applications at the same time so that everything looks right all the time?
Thank you for your help!
Are you saying that I need to activate a soft-proof in photoshop choosing the newly created profile in order to see the image correctly? … Do you mean that I need to activate soft-proof for every single image as I work on it to ensure I’m seeing it corectly? … What about editing in Adobe Camera Raw? What about viewing images in other image viewers (Honeyview) that only allow for viewing through the moniitor’s .icc profile? Will it still be displayed correctly?
What exactly is happening here? … All I want to do is create 3 seperate .icc files to be used while editing\viewing in 3 different lighting environments… 3 .icc files which contain both a color profile and a claibration… So that both are being applied to the image.
I don’t get why I have to do a gamut transform and a soft proof to accomplish this…. I’ve been viewing and editing images through the .icc file (color profile\calibration) just fine up until I wanted to make room light adjustments… You say that the color managed application usually uses the source .icc file. Does this mean that I was never actually seeing the corrected presentation of my images. (With the default .icc files I was creating before I tried to change the lighting conditions aspect of it’s creation?)
Wordy, I know, sorry, but I truly need to understand this… I am desperately trying to figure out exactly what’s going on here.
🙂
What exactly is “The source profile” in a color managed application? … I think this is where I’m getting confused.
Could you please explain this to me in simpler terms… I’m getting close to putting it all together.
Do I need to start over and do two more a calibration\profile combos from scratch for both?
You can just change the profiling settings and then use “Create profile from existing measurement data…” in the options menu and select the existing profile, then save to a new name.
Do I need to change that setting to ‘normal monitor’ for one, and to ‘bright monitor’ for the other?
Yes.
What can I do to make non-color managed apps and Windows look better in my new situation?
In that case, there’s no way around new measurements, with the calibration settings changed accordingly.
OK, the more I study this, the more I’m beginning to see what’s going on… So, you’re saying that in color managed applications (applications which use the monitor’s profile) Won’t use the gamma curve created in the normal way.
The way color management works is by reproducing the source tonality in the destination (in this case the monitor). So, the monitor tone response needs to be known for this of course, but it doesn’t need to match the source.
So if I want to make room-light adjustment changes to the gamma curve used by color managed applications, I need to recalculate a new gamma curve in the gamut mapping options to create a gamma curve that it can use. And it is here, in the gamma mapping options that I have a choice to create a curve for different room-light conditions (High, med, low).
Sort of. The gamut mapping influences how the source is mapped into the destination, and changing how that mapping is done using the CIECAM02 options is to some extent comparable to a gamma change of the source.
It seems like these choices (high, med, low) are a bit arbitrary
These are the three “common” viewing conditions defined in CIECAM02. You can find more technical information (e.g.) on Wikipedia’s CIECAM02 page.
And what about getting the same results in non-color managed applications at the same time so that everything looks right all the time?
This can be difficult and may require some experimentation.
Are you saying that I need to activate a soft-proof in photoshop choosing the newly created profile in order to see the image correctly? … Do you mean that I need to activate soft-proof for every single image as I work on it to ensure I’m seeing it corectly?
Yes. Once setup, you can assign a keyboard shortcut to toggle softproof, or record an action in Photoshop and assign the shortcut there.
What about editing in Adobe Camera Raw?
I think you can activate softproof in ACR, not sure though.
What about viewing images in other image viewers (Honeyview) that only allow for viewing through the moniitor’s .icc profile?
Depends wether they allow setting the rendering intent to perceptual.
I don’t get why I have to do a gamut transform and a soft proof to accomplish this
Gamut transforms are always performed by color managed applications. But you need to use perceptual intent to see the effect of the CIECAM02 mapping that you created, and different applications may have different means to do this (or none in the worst case).
You say that the color managed application usually uses the source .icc file.
Yes, but not exclusively: A color transform always incorporates at least two profiles, usually source (the image profile, e.g. sRGB or AdobeRGB) and destination (in this case the monitor profile).
Does this mean that I was never actually seeing the corrected presentation of my images. (With the default .icc files I was creating before I tried to change the lighting conditions aspect of it’s creation?)
You were always seeing a color managed result in color managed apps, but the default colorimetric transform simply does not take into account differing viewing conditions.
What exactly is “The source profile” in a color managed application? … I think this is where I’m getting confused.
In the case of an image viewer or editor, the source profile is that of the image, e.g. sRGB or AdobeRGB.
