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HI! I’m having issues with a Dell monitor that only have brightness control. The device native temperature is like 4500, not sure why they make such abomination, so I set the target to be 140 cd/m2 and with the interactive calibration I set brightness to the next possible on the high side to 140, in this case is 149, but after finish calibration the result is 100 cdm/m2 +/- and if I check uncalibrated the monitor is on 149, check calibrated, 100…. now look at the screenshot of the RGB interactive, you will see the native blue of this monitor is super low. Can it be that becuase the native blue is so low that the calibration is having to lower R and G to the point of B to reach a white that is actually white? and that ends being 100?
How are those RGB measurements taken? at R G B at 100% I guess right? because is the whitest point the monitor can reach at that moment right? So, if this is the case, and monitors that do not have an RGB gain control, shouldn’t be the instructions, raise your brightness until at least one of the R, G or B, hit the center mark?
Can it be that becuase the native blue is so low that the calibration is having to lower R and G to the point of B to reach a white that is actually white? and that ends being 100?
Possibly. You can check the calibration curves to see how much R and G needed to be lowered.
[…] shouldn’t be the instructions, raise your brightness until at least one of the R, G or B, hit the center mark?
Not sure what you’d expect this to do – or did you mean “raise brightness until all of R, G and B hit or exceed the center mark”, to give headroom for lowering of channels via the calibration curves and still hitting the desired target white level? In which case that wouldn’t work, because the ratio of R, G and B are usually not influenced much by the backlight (unless the backlight chromaticity changes at different levels).
I see what you mean, I raised the brightness and it didn’t changed the proportion of the RGB. It would be cool to have a way to reach the right level of brightness to compensate and get the right headroom. I’ve tried twice going through the whole process and still can’t get the right amount, and then how do you know you are not going too high and wasting precision. Case the higher we go, if briegthness needs to be adjusted by lowering the LCD instead of the backlight, then we could end with a monitor with the precision of a 5 bit monitor 🙂
the native white point of this monitor is way too far of where I need it. I think is time to change it.
I’ve tried twice going through the whole process and still can’t get the right amount
Did you try around 196 cd/m2 (140 * 1.4)?
if briegthness needs to be adjusted by lowering the LCD instead of the backlight, then we could end with a monitor with the precision of a 5 bit monitor
A valid concern. The videoLUTs are limited bit depth, and if they are only 8 bits effective to start with (depending on the card and connection) you may already introduce banding.
