Originally Posted by umr
I find luminance so key it is a parameter I would never sacrifice since it compromises resolution, color and visual impact. In other words I suspect an excellent 1080p rig would probably best a poorly done 4K rig. Just like megapixels and camera image quality at not highly correlated.
Exactly. We have to figure human perception into whatever we want to achieve, not just tech specs like resolution. Brightness and contrast impact our ability to perceive detail. Depending on how dim you allow your set up to get, you are in a real, perceptual sense "throwing away resolution" to some degree (because you are lowering the amount of light and hence detail you will perceive).
This was really brought home to me when comparing screens. I had the Da Lite High Power and compared it to some other screens, like a (effectively) nuetral white screen. On close inspection the pixel structure was resolved more finely on the neutral gain screen. Close up I could see how the HP screen's optical coating created a hazy, blurred effect with the pixels. Viewed that way, one would expect that, if anything, the neutral gain screen would make for as sharp, or a sharper image.
But from my regular viewing distance it just wasn't so. The Brightness difference with the HP engorged my eyes with yummy photons of picture information. The image looked distinctly sharper, with significantly more visible detail, and MUCH more color detail. (E.g. some scenes from Gladiator in the forest showed so much more detail, and color variation among the foliage, trees and rocks, on the HP screen).
That has held true for all the higher (even slightly higher) gain vs lower gain screens I've compared, so long as there is a visible brightness difference.
But had I been able to have an equally bright image on the neutral gain screen, no doubt it would have had similar looking detail and sharpness (if not, perhaps, a bit more).