I need to get my luminance to around 105 cd/m2 to match print brightness under display conditions (printer is profiled). I'm calibrating a Dell 2209WA with a Spyder 3 Elite (gamma 2.2, 6500K). The monitor factory defaults are brightness=75, R/G/B=100.
I found that if I calibrate leaving the RGB values near the factory default (say 93/96/94 after calibration), and lower the brightness to 10, I'm still way too bright, 140 cd/m2. I can hit the target by also lowering the RGB values together, though. (For example, to hit the luminance target my current calibtated settings are brightness 40, RGB 75/77/74, dap is 0.05.)
So my question is, should I calibrate by lowering brightness to 10 (or even lower) and going the rest of the way by lowering RGB; or doing it the way I am now setting brightness nearer the middle; or even leaving brightness up near the default and just lowering RGB values? Or does it make any difference in the end anyway?
Physically, what is the difference between the two types of adjustments? I believe lowering brightness just dims the backlight. What does lowering R or G or B do hardware-wise.
Thank you for shedding light!