>> Actually, after thinking about this for a while longer, it occurred to >> me that per-pixel gain and offset may be all there is to it. [ ... ] >> > > Being able to sense and apply per-pixel gain will lead to a normalized > output per pixel but it still can't negate thermal and other random > noise sources. > Precisely. >> I still think that using terms like "Dynamic Range Expansion" [ ... ] >> > > As you can likely appreciate 22bits is way over the top for most any > analogue sampling system Yes. It seems right in a setup like this to use enough bits to make sure *all* the info (including noise) is kept. And the circuit is probably also designed for larger sensors with more dynamics... > and in the case of these types of sensors > probably at least 8 bits more than is necessary to capture the signal > over the noise floor. [ ... ] > The D range expansion really refers to non-linearizing the > extremes of the capture range, IE softening the transfer curve at the > noise floor and at saturation which should as suggested provide a more > film like rendering. > Ah. So that's what the gamma block refers to? Yes, it does seem nice to be able to do such things at this level, although I'm not sure it *really* expands the range. > [ ... ] > > They do but I think it's a lot more rudimentary than the options that > this chip offers. > Yes. Just applying one common offset and gain factor, perhaps, or one per colour channel? (The gain would probably be combined with the ISO setting...)
- Toralf -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
