Digital BW, The Print

> From: Steve Kale
>
> As a point of clarification, I believe what concerns the user most is the
> usable dynamic range delivered by the camera - not the dynamic
> range of the
> sensor ignoring all other aspects.  I have always found it puzzling that
> Canon has not moved to delivering the user 16 bits and had always assumed
> that the issue was processing speed.

<snip>

> The question that concerns my original post is whether or not, all
> else being equal, an increase in bit depth provides greater usable dynamic
> range to the user.

It won't. The extra bits will be utter garbage.

I did some rigorous tests on my old Minolta DiMage 7 camera, which has an
uncompressed raw format, making it easy to manipulate in software. Its
sensor, under the best (broad daylight) conditions has eight bits of dynamic
range, because masking off the bottom four (out of 12) bits of the raw data
made absolutely no visible difference in the image. I'd say that my Canon
10D has about ten bits, based on the ratio of noise levels, so increasing
the A/D resolution beyond 12 bits would be useless. And if 12 bits is two
more than necessary in the 10D, I doubt there are any DSLRs out there yet
that really need more than 12.

--

Ciao,               Paul D. DeRocco
Paul                mailto:pderocco@...