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Hello everyone. For the first time I’m going to calibrate and profile my monitor. I have a big doubt about the process and I’m pretty sure I’m missing something. I have the possibility to adjust RGB gain by using the monitor OSD, so I decide to tick the “interactive display adjustment” in the calibration window. It means that once that white point, brightness target and gamma have been chosen from the calibration menu, the SW asks to adjust RGB gain and brightness by using the monitor OSD in order to get the targets previously chosen. Having said that, I need two different kinds of calibration with different targets (for two different purposes). Let’s call them:
CALIBRATION “A” with white point “A”, brightness “A” and gamma “A”
CALIBRATION “B” with white point “B”, brightness “B” and gamma “B”
This means that when I start the calibration process for the target “A”, I will have to adjust the RGB gain and brightness in a certain way. At the end of the process, I will get an ICC profile “A”. Then, when I start the calibration process for the target “B”, I will have to change the RGB gain and brightness since the target is now different.
At the end of the process, I will get a new ICC profile “B”. Now in the monitor I have the last RGB and brightness settings (i.e. those I used for the calibration “B”) and the ICC profile “B” activated in Windows.
My question is: when I switch back to the ICC profile A, how it will behave since the RGB gain and brightness of the monitor are those used for the calibration B?
I hope I explained myself.
Thank you!
My question is: when I switch back to the ICC profile A, how it will behave since the RGB gain and brightness of the monitor are those used for the calibration B?
It may behave bad if ypu rely on GPU to correct whitepoint, since it is applying a small correction for A, while settings are for B.
If you trully got “all green” on RGB gains popup and we assume zero or near zero GPU whitepoint correction and also monitor behavior is near ideal, I meant that uncalibrated gamma ramp is exactly the same on 2 different RGB settings & brightness, then you’ll get Whitepoint B, gamma A.
Since color managed apps won’t care about WP, all rendering from image to screen are relative whitepoint intents, it won’t matter (regarding RGB color transofrmation maths) taht your profile is A but whitepoint is B. Of course any attempt to use abs colorimetric on LUT3D won’t match. Also we assume that A and B have the same colorspce, you are not messing with A=sRGB simulation and B=P3 or native or something like that… it won’t work properly.Anyway… measure it and test if your display behaves so close to ideal behavior on that situation (OSD=B, profile = A), run a profile validation with no colorspace simulation at all and ignore “measured white vs profile white” test.
This is an issue I can’t find addressed anywhere online! Is this similar to what you are describing: Reset monitor to factory settings and create a new icc profile using calibration software. During the calibration, you have to manually adjust the monitor’s rgb, brightness & contrast, guided by the calibration software. Now, you have a new icc profile. All fine. But then…. you need to create a 2nd icc profile that includes a different gamma (example). You cycle thru the calibration, and change the OSD settings again, which destroys the prior icc profile, because that profile was based on the prior OSD settings, which are now changed! What a mess. I’ve been searching for hours over a week’s period and can’t find any answers. Your post was the closest I’ve got, but the guy that replied to you was just grasping at straws and is also stumped. My conclusion is: Unless the icc profile can control the monitor’s OSD settings, (which they can’t) you simply can not toggle between 2 different icc profiles without manually changing the OSD each and every time. I’m hoping some genius sees this post and knows how to correct this mess. It does seem everybody that is making icc profiles is basing them on the prior monitor settings and when they switch back, all the prior icc’s are now damaged. How could this be in today’s modern world of computing? I’m a total noob, so I hope I’m wrong, but using my Vulcan brain, I do think there is a major problem.
Think outside the box. 1 way -A tv has picture modes and 2 to 4 hdmi inputs. There is a hdmi switch. 2nd way- a color box to hook up a monitor with many inputs and one output. 3rd way- Just calibrate all the profiles you need on one rgb white balance setting on the monitor. The same black point and same white point. Your black point and white point change adjusting backlight brightness so you use backlight to manual put brightness where you want. It wont be perfect but it will be close. Backlight barely changes rgb balance. Do not change contrast or black level. You can remember the settings and put it back and forth for profiles. Display cal can adjust brightness with lut but it changes the contrast ratio. Backlight does not change contrast much. Perhaps worse at the extremes of backlight range.
“It wont be perfect but it will be close. ” Well, thanks, but it does seem to be a huge error in the design of the software that lacks control over the monitor’s OSD when creating a new ICC profile. Hard to believe all the companies that make monitor calibration just couldn’t figure this one out.
Sorry Steven. I am not the designer. You do not have to change brightness and contrast for more than one calibration. Usually, it is left alone. Usually, you keep RGB the same for more than one profile since it is controlling the Temperature. RGB is done with display Cal.
It will be close enough your eyes and brain cannot tell.
There is no way to control the monitor with a ICC profile. There is no logic in the real world. Creators make devices the way they want. Display cal is the best there is. It can do lots of calibrations and work on lots of devices. Very big manual. The monitor could be special like Samsung’s magic osd and use Pc mouse to control the monitor. A special programmer could in theory change profile and change the monitor with software on that setup. It was a pain having software control my Samsung syncmaster 2053B .
How about going from an icc profile with gamma 2.2 and a 2nd one at gamma 2.6 ? You’re saying changing the brightness isn’t noticeable?
Yes, the backlight brightness doesn’t change the gamma and rgb enough to matter visually. 2.6 gamma wow. I did go from 2.0 to 2.4 before and display Cal worked it out. The first rgb of 0 to 255 – 1 will be a fraction of 1 to make 2.6 and at 2.2 will be + or – around 1. I like looking at the lut table. Once had 1 set to 0 since display was so bright when brand new. Sometimes some rgb numbers 100 and 101 were the same number, i am guessing which ones. Overtime perfect calibrations do run out monitors slightly change. They can change in 24 hrs or a month.
Well, there is only one solution that is 100% on point. Wipe the monitor settings, remove any icc in the windows CM. Windows will now use the internal default icc which is sRGB. Now calibrate, create new icc and write down the new monitor settings. Then repeat same steps for the 2nd icc creation. Now, every time you want to switch icc’s you have to change the monitor settings to that particular icc before loading it. Only takes less than a minute to alter the monitor settings. 100% accurate, can be used to create dozens of icc profiles, no ifs ands or butts.
It depends. On good quality screens, changing white point and brightness doesn’t have too much effect, you can use ICC A with whitepoint B and brightness B. I usually check with the verify function, using ICC A as the setting, simulation profile is sRGB. If the delta E of any grayscale is greater than 1, I will do another ICC for whitepoint B and brightness B.
Thst doesn’t sound right. I would think a different white point would throw everything off, no?
White point is the color temperature. You calibrate to a white point so white point is a preference. Blue and Red effect white point the most. White point would not affect calibration if you needed changed.
By the way changing my brightness backlight from 35 to 80 goes from 91cdm2 to 170cdm2. The delta E does change 0.2 and blue, white balance goes up on higher brightness 1%. So its temperature changes. Seems like 35 to 80 would give more brightness but the screen is working harder and near its highest brightness available. My numbers are estimates.
