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datadump
4th of May 2009 (Mon), 18:37
How does the driver settings Brightness/contrast play into monitor calibration?

i'm finding that my benq 241vw is too bright. i cannot get it dark enough. so i tried playing with this. but i found that it gets overridden after booting up and logging into windows vista.

when i play with the sliders again, shows that the monitor can do darker.

gcogger
4th of May 2009 (Mon), 19:00
What those controls do is adjust the graphics card lookup table (or LUT) which will adjust the RGB values before they are sent to the monitor. As an extreme example you could adjust them so that, when you try and send RGB values of (255,255,255) to the monitor the LUT maps that to (127,127,127), and the monitor will appear darker. Unfortunately, the blacks will not be any blacker, so you've just halved your contrast ratio.

The most likely reason the settings don't stick is because of your monitor calibration software. Every monitor calibration system I am aware of uses the graphics card LUT to get things like the gamma and colour neutrality correct. There will probably be an application that runs on system startup (e.g. the i1 'Logo Calibration Loader') that loads a LUT to the graphics card - this will 'overwrite' the adjustments you have made in the nVidia control panel, as the graphics card can only use one LUT.

You can achieve the same affect with the monitor's controls. Assuming you've already dropped the brightness as low as it will go, try reducing the values of the RGB sliders. This has the same effect as using the nVidia control panel. If you are adjusting the sliders to get the correct colour temperature as part of the calibration then simply start with all 3 values at a lower level than you were before. Now theoretically, doing this will (as with the control panel method) increase banding on gradients in your images; but we have been discussing this in recent threads and any such effects appear to be very subtle.

S.E.V.
4th of May 2009 (Mon), 19:00
Did you adjust the brightness on the monitor end? I would imagine that those controls through nvidia controls the feed coming out of the video card.

datadump
4th of May 2009 (Mon), 19:07
thanks guys.... i will try the RGB trick... they are by factory 50 50 50. i dont use RGB sliders in my calibration because i find it is worse than just letting the cal set it....

datadump
4th of May 2009 (Mon), 19:21
is there a way to ORDER the startup exe's?

msconfig u can enable/disable startup items but u cant ORDER them.
i should make sure the calibrator tool is LAST ( right?)

datadump
4th of May 2009 (Mon), 19:36
this is weird...

every other bootup, i get nvidia driver sliders taking over than the calibrationloader.ext from my calibrator. i goto the xrite folder and run Calibrationloader.exe again and it restores my calibrated settings again... is there a way i dont have to do this?