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Hello everybody,
I’m rather new to the calibrating world and after reading a ton of guides and articles online (including the DisplayCal docs) I have a question I’d really appreciate some help with.
TLDR version:
From my understanding the DisplayCal generated ICC profile that I load via the DisplayCal profile loader only corrects the tone curve / gamma. No other corrections, like moving the colors around to get right hues and such, are applied. Would that be right?For context version:
I am asking because of the following situation.I have the LG 40WP95C-W which supports hardware calibration via LG’s studio. Unfortunately calibrating it via their app (using the i1 display pro) gives me a rather paltry gamma calibration and I loose a lot of detail in the darks (0 RGB to 16 RGB values are practically the same shade).
So what I’m doing now is I’m doing a hardware calibration pass and then on top of that I’m also doing a DisplayCal pass meaning I also end up with a DisplayCal ICC profile which, if I validate it with DisplayCal, gets me the perfect gamma curve – dark colors look much more as expected now.
Due to my lack of knowledge however I am now a little bit unsure if the above is the correct procedure – I am worried that with the ICC profile loaded in Windows via the DisplayCal profile loader the gamma curve gets corrected but from my understanding that should only correct the gamma curve but then I’m wondering what happens to the actual colors? Shouldn’t they be also corrected to account for the gamma change?
Important note, the monitor is in sRGB mode via OSD because that is the color space I’m targeting (it is also what it is HW calibrated to).
Unfortunately I use a lot of non-color managed apps in my workflow and precisely because of this I’m afraid these apps potentially just load the gamma correction from the ICC but not how the colors should shift to account for that.Any help would be greatly appreciated.
Calibrite Display Pro HL on Amazon
Disclosure: As an Amazon Associate I earn from qualifying purchases.The way to see what gamma curves do is to see them. Every screen is different. You can see if the gamma curve starts at 256,256,256 or close with the profile info button in display cal profile loader. Choose a gamma curve that matches the hardware curve in the low RGB 0 to 128. You won’t lose black detail then. Blue at 10 RGB is the lowest I can see. SRGB and bt 1886 is the only gamma that is not flat so takes the screen black level into account it try not to lower rgb 1,1,1 as much as others.
I prefer a flat gamma with a slope at the end to match the 5% and 10% since my blue in white is raised at 5% with controls at 0. I move controls for blue to -5 at 5% and it matches gamma 2.2 . I miss seeing blue at 11 and start seeing blue at 15RGB. I choose bad delta e at 5% and seeing blue much as I can. Helps to see detail in very dark colors.
The profile moves colors in color managed apps.
Hope I do not ramble to much.
I recomend a hardware pass and then run display display cal using as measured. You can set the color temperature. It generates a color profile for color managed then. It will be good if you keep gamma the same and do touch up the hardware more over time. Funny how hardware decides to be different on its own. Sometimes its your meter since it not properly set or exacly the way it was before. I wonder if they get any dust at all in them.
Hello everybody,
I’m rather new to the calibrating world and after reading a ton of guides and articles online (including the DisplayCal docs) I have a question I’d really appreciate some help with.
TLDR version:
From my understanding the DisplayCal generated ICC profile that I load via the DisplayCal profile loader only corrects the tone curve / gamma. No other corrections, like moving the colors around to get right hues and such, are applied. Would that be right?Yes
For context version:
I am asking because of the following situation.I have the LG 40WP95C-W which supports hardware calibration via LG’s studio. Unfortunately calibrating it via their app (using the i1 display pro) gives me a rather paltry gamma calibration and I loose a lot of detail in the darks (0 RGB to 16 RGB values are practically the same shade).
Maybe that’s what you asked for.
IDNK that display but I assume that’s the typical 1000-1500:1 IPS. If you want to keep X power law > 2.2 @100nit, some darker greys will be packed in 0.1 -0.2nit baceause you asked for accurate tracking of high value gamma.
Also your visual inspection is not reliable bc it should be done non color managed *if* it caused by calibration.So what I’m doing now is I’m doing a hardware calibration pass and then on top of that I’m also doing a DisplayCal pass meaning I also end up with a DisplayCal ICC profile which, if I validate it with DisplayCal, gets me the perfect gamma curve – dark colors look much more as expected now.
It’s the tyìcal solution for unreliable HW calibration monitors like Dell, Lg, MSI, Benq… although most of you end there because color cast in greys rather than innacurate gamam value.
Due to my lack of knowledge however I am now a little bit unsure if the above is the correct procedure – I am worried that with the ICC profile loaded in Windows via the DisplayCal profile loader the gamma curve gets corrected but from my understanding that should only correct the gamma curve but then I’m wondering what happens to the actual colors? Shouldn’t they be also corrected to account for the gamma change?
Color managed, yes. Color managed module will use display porfile information (displaycal’s) as actual display description. Using single gamma curve + matrx will match colsely whetever you got with monitor vendor software.
Important note, the monitor is in sRGB mode via OSD because that is the color space I’m targeting (it is also what it is HW calibrated to).
Unfortunately I use a lot of non-color managed apps in my workflow and precisely because of this I’m afraid these apps potentially just load the gamma correction from the ICC but not how the colors should shift to account for that.Any help would be greatly appreciated.
DWMLUT (full LUT3D calibration, dithering = bandless) or AMD/novidoe_sRGB for matrix-lut sRGB simulation
DWMLUT:
1) use LG software, calibrate to native gamut, desired white, closest to natuve gamma
2) calibrate &profile in DisplayCAL, whitepoint correction optional using better colorimeter correction, XYZLUT profile
3) create synth profile native gamut (from custom porfile illuminant relative RGB primaries) or in your situation just use sRGB porfile no need to create that synth profile.
4) create LUT3D from custom profile to synth profile (or sRGB profile in you case)
5) load LUT3D and assign in OS the generic/synth profile you are simulatingFirst off, an immensely big thank you to the both of you for taking the time and sharing your knowledge. I really appreciate it!
It seems like because I rely on non-color managed apps the DisplayCAL + DWMLUT approach seems to be the way to go for me.
Fortunately I am only concerned with the sRGB color space looking correct on screens that have an actual sRGB emulation mode. Can’t imagine handling all of this science and also have to convert between spaces 🙂
@Vincent I hope you don’t mind but if you can spare a few more minutes, I’d just like to double check if I indeed do understand things.– As per my understanding, with the above DWMLUT instructions, I am still expected to have the ICC profile loaded in the DisplayCAL Profile Loader so that the tone curve gets corrected (even for non-color managed apps)?
If so, wouldn’t that incorrectly affect color managed apps because then they’ll get corrected once by the ICC profile + the DWMLUT resulting in double applied corrections?– With the above in mind, I can also choose to bake the VCGT into the 3DLUT which I suppose would mean I should skip the ICC loading and just have everything driven by the DWMLUT itself?
– And just for my own personal curiosity and understanding of things… The ICC profile contains the VCGT (tone curve / gamma correction) + color space conversion data (if going from say DCI-P3 to sRGB) + alongside that also color corrections (so that slightly offset red is actually as red as it should be)?
As a side note, regarding the screen itself, yes, you’ve pretty much nailed it. The LG is measured at 1000:1, it is the regular Nano IPS type panel and not the newer IPS Black one.
I also have a 57″ Samsung G95NC which I’m quite a fan of but can’t use for work because non-colored managed apps don’t support ICCs and the display itself doesn’t support HW calibrating at all (’tis a gaming screen after all).
After DisplayCAL calibration and profiling it does really great with a dE at 0.6 (pre cal it is at 1.8, max dE at 7!) with measured contrast at 2400:1 although because it is a VA panel the viewing angles (mostly the vertical ones) are obviously a bit problematic. Nonetheless, I am intrigued if I could get it working with the DWMLUT method because the screen real-estate is something else. Viewing angles are less of a problem if you mainly do your edits at the middle of the screen I’d say 🙂Thank you kindly!
First off, an immensely big thank you to the both of you for taking the time and sharing your knowledge. I really appreciate it!
It seems like because I rely on non-color managed apps the DisplayCAL + DWMLUT approach seems to be the way to go for me.
Fortunately I am only concerned with the sRGB color space looking correct on screens that have an actual sRGB emulation mode. Can’t imagine handling all of this science and also have to convert between spaces 🙂
@Vincent I hope you don’t mind but if you can spare a few more minutes, I’d just like to double check if I indeed do understand things.– As per my understanding, with the above DWMLUT instructions, I am still expected to have the ICC profile loaded in the DisplayCAL Profile Loader so that the tone curve gets corrected (even for non-color managed apps)?
If so, wouldn’t that incorrectly affect color managed apps because then they’ll get corrected once by the ICC profile + the DWMLUT resulting in double applied corrections?No, if you use DWMLUT you cannot use custom profiles. read above. Display profile is the idealized colospace you try to simulate.
– With the above in mind, I can also choose to bake the VCGT into the 3DLUT which I suppose would mean I should skip the ICC loading and just have everything driven by the DWMLUT itself?
It is the way to use it, unless GUI for resolve keeping system wide gammacalibration and things like that.
– And just for my own personal curiosity and understanding of things… The ICC profile contains the VCGT (tone curve / gamma correction) + color space conversion data (if going from say DCI-P3 to sRGB) + alongside that also color corrections (so that slightly offset red is actually as red as it should be)?
no. display profile will be srGB or P3 if using DWMLUT. It stores nothing ,just adescription of that idealized proifle. LUT3D simulates that.
As a side note, regarding the screen itself, yes, you’ve pretty much nailed it. The LG is measured at 1000:1, it is the regular Nano IPS type panel and not the newer IPS Black one.
I also have a 57″ Samsung G95NC which I’m quite a fan of but can’t use for work because non-colored managed apps don’t support ICCs and the display itself doesn’t support HW calibrating at all (’tis a gaming screen after all).
After DisplayCAL calibration and profiling it does really great with a dE at 0.6 (pre cal it is at 1.8, max dE at 7!) with measured contrast at 2400:1 although because it is a VA panel the viewing angles (mostly the vertical ones) are obviously a bit problematic. Nonetheless, I am intrigued if I could get it working with the DWMLUT method because the screen real-estate is something else. Viewing angles are less of a problem if you mainly do your edits at the middle of the screen I’d say 🙂Thank you kindly!
Awesome, I think I know now where I went wrong with my previous line of thinking. Thank you!
That said, regarding the 3D LUT creation process, I’d still appreciate some help.
– The source space I assume is the sRGB IEC profile?
– Destination profile would then be the generated .ICM after calibrating & profiling in DisplayCAL?
– And I’d kindly like to ask for your suggestion regarding the tone curve. Should I opt for the black offset at 100%? I’m quite focused on getting the black-ish end of the spectrum looking “correct” but from my understanding, especially on the LG (which has a fairly limited 1000:1 contrast ratio) that will be more difficult? Unless I’m understanding things wrong the VA panel (2800:1 after cal) should technically perform better here.
Thanks again!!
Awesome, I think I know now where I went wrong with my previous line of thinking. Thank you!
That said, regarding the 3D LUT creation process, I’d still appreciate some help.
– The source space I assume is the sRGB IEC profile?
Whatever you want to simulate
– Destination profile would then be the generated .ICM after calibrating & profiling in DisplayCAL?
Yes, an accurate description of display, better if XYZ lut (densely populated 3d mesh)
– And I’d kindly like to ask for your suggestion regarding the tone curve. Should I opt for the black offset at 100%? I’m quite focused on getting the black-ish end of the spectrum looking “correct” but from my understanding, especially on the LG (which has a fairly limited 1000:1 contrast ratio) that will be more difficult? Unless I’m understanding things wrong the VA panel (2800:1 after cal) should technically perform better here.
Thanks again!!
Whatever you want to simulate, taking account of display limitations. But since display profile on OS will be source profile, do not deviate too much or color managed apps will show wrong colors.
