[silentplummet]

Bit depth is not a measure of quantity, but of dynamic range. In other words, what matters is not only how many quantization steps you have, but how large of a space you are trying to map them over.

The examples in the article point to this obvious conclusion, but don't quite state it explicitly. The relationship between space and quantization effects is demonstrated for a physical dimension interpretation of space by the horizontal greyscale bar that stretches and contracts.

But what if you stretch and contract the dynamic range of your monitor itself? Each bit in the encoding space (naively) offers a doubling of dynamic range in the natural space, so even your 30 bit encoding can be stretched if you display it on a monitor that intends to output a contrast ratio many times greater than what we are used to.

For instance, imagine a monitor that could output light perceptually as bright as the afternoon sun, next to effectively infinite blackness. Will 30 bits be enough when 'stretched' across these new posts of dynamic range, or will banding (quantization) still be visually evident when examining a narrow slice of the space?

[corysama]

HDR monitor do exist. BrightSide Technologies was showing them at SIGGRAPH over ten years ago. Looks like consumer OLEDs are starting to get on board [1]. And, they did really want 10 bits per channel. But, even that seems lightweight.

10 bits per channel will carry us for a while. Apparently Dolby bought BrightSide and now they are pushing for 12 bits. 16 bit ints will probably be enough for home use in practice. Internally, most games that do HDR rendering use 16 bit floats for their intermediate frame buffers. That format is popular in film production as well. I would be surprised if consumer display tech ever bothered to go float16-over-DVI. But, maybe it will get cheap enough eventually that we might as well have the best :)

[1] http://www.avsforum.com/forum/40-oled-technology-flat-panels...