CompuServe Thread

John, Not to beat a dead horse, but basically it boils down to this. Everyone has a different monitor. So in order to create some semblance of uniformity the Gamma Boxes were created to help in determining a default setting for monitors. Unfortuneately, its a little more complicated than the boxes can fully account for though the Yost Group did there best with what is currently possible. If we all just worked in the SVGA environment it would be fairly straightforward as it is with programs like photostyler etc. The problems arise with different monitors and different display cards and different framebuffers. What works for your Display card won't necessarily and probably won't work for your Framebuffer. Then to make matters worse when working with NTSC, NTSC has gamma correction built in to its specifications, to its damn near impossible to make this box thing work. Here in lies the greatest challenge. So you add all these factors together and what do you get, mass confusion! It took several of us with extensive video background to go through manuals contact video engineers and equipment managers to come up with values that work in the video domain. The Targa 32+ was a big problem because by default it gamma corrected because at a resolution of 512×486 it conformed to NTSC specs, which inherently compensate for gamma, also known as hardware gamma correction. Because 3DS's gamma correction is superior it took about a month to find out the best way to get it disabled so that the 3DS gamma correction could be utilised. Without making this anymore long winded than it is, suffice it to say each piece of equipment on the video side had to analyzed to determine what its affect on 3DS gamma was. Many video devices like VTR do not do gamma correction but some do. The PAR fortuneatley doesn't and the AT-Vista doesn't. Then different Video monitors need different amounts of correction. So you have to experiment to see what works best for you. If you ask what different people have their gamma set at you'll get a variety of answer's. Anyway, glad you're not frustrated by it, and you can achieve some really outstanding results when you've got it right. So its well worth the effort. -JE

Regarding the gray boxes, what you have there is simply a single-pixel checkerboard inside a medium-gray border (or is it the other way around?). Anyway, the checkerboard consists of alternating black and white pixels that appear to be medium gray at any distance. As you adjust the display gamma, 3ds alters the luminance of the solid gray. If there was no such thing as a gamma curve, and all displays were completely linear (don't we wish), a solid gray value of 127,127,127 would appear the same as the black and white checkers. Theoretically, when you adjust the solid gray to match the _apparent_ gray of the checkers, your display gamma should be balanced. In reality, we've found that certain monitor displays don't always work like that. NTSC monitors, for example, often throw things off. It may be that your monitor is bleeding the pixels slightly (ouch) so the black/white checkers appear a different value of gray, etc., etc. If, as you say, you like "twidgeting," you could try rendering a checkerboard that's 2×2 pixels and check it out from across the room while squinting your eyes. Since gamma is a voodoo art, you might want to first sprinkle some chicken blood on the keyboard. – Jack