First off -- thank you for this conversation. It has caused me to think more-deeply about the meaning of pixel-values in a display context. It has sent me into

First off -- thank you for this conversation. It has caused me to think more-deeply about the meaning of pixel-values in a display context. It has sent me into the standards, too. In particular, I found this document useful: http://www.color.org/WP40-Black_Point_Compensation_2010-07-27.pdf http://www.color.org/WP40-Black_Point_Compensation_2010-07-2... We agree that bit-depth is independent of maximum light output. Where we appear to disagree is on the meaning of an ideal bit, in particular whether or not it is acceptable for the (gamma-corrected) intensity difference between pixel-value 0 and pixel-value 1 to be greater than the base intensity of the display at pixel-value 0. I believe that I'm arguing for the concept depicted in Figure 3 of the document above (relative colorimetric), while you are arguing for the concept in Figure 4 (black-point compensation). There is an important pragmatism to your approach -- high contrast ratios are technically difficult, while higher-resolution gradations sitting atop a pedestal of minimum intensity may be more technically-feasible. Increased subdivisions between minimum intensity and maximum intensity do reduce banding, as you suggest. Such a rendering choice can portray the content of an image at the expense of the creator's intended contrast. A linear display output with no offset will yield an intensity proportional to the intensity value assigned to that pixel. Higher bit-depth does not make for greater intensity, but rather more gradations between maximum intensity and zero. As a scientist or as an artist, when specifying pixel values I expect the intensity, on a calibrated display, to reproduce a calibrated fraction of the maximum light intensity. It is helpful to understand that not all systems render with this intent. In the original reply, the thought-experiment display had a minimum brightness of 1 nit and a maximum brightness of 100 nits and 255 brightness levels between them. That spans a factor of 2^6.7. The discrepancy between our opinions represents differences in a choice of rendering intent. If I had to specify the rendering strategy for portraying 8-bit pixel values on such a display, it would have less contrast in the shadows than the highlights but equal contrast in the highlights when compared with an 8-bit display with a minimum brightness of 0.4 nits and a maximum brightness of 100 nits (which is capable of 2^8 dynamic range). Your strategy would yield uniform contrast spanning the shadows and highlights, but less contrast on the 1-100 nit display than the 0.4-100 nit display. In that situation, I suspect that most people would prefer your black-point compensated rendering strategy, as the shadows would not be crushed. I simply wouldn't market/sell it as a true 8-bit display, though I understand why a manufacturer would choose to do so. Thank you -- I learned something useful.