On 12 April 2010 15:30, Oliver Tonnhofer <o...@bogosoft.com> wrote: > On 12.04.2010, at 14:34, Sebastian Haase wrote: >> My point was also, that I would doubt that there is physically(!) more >> information than 16e6 possible values per pixel. >> A digital gray scale CCD camera with more than 12 bits costs multiple >> 1000s of Euros or Dollars... > > Every current DSLR camera has more than 8bits per color, a Canon EOS 450D > has 14bit for example.
That's linear bits though. Once you add a companding curve (like a gamma) to it, you can get away with many fewer bits than that. As a rough guide, a high-quality uncooled CCD is good for up to about 12 bits linear, or 8 - 10 bits with a gamma. Most flatbed scanners use a line sensor with rather a short exposure time (only a few ms) to keep the scan-speed up. As Sebastian says, you are unlikely to be getting more than 8 bits of signal. John _______________________________________________ Image-SIG maillist - Image-SIG@python.org http://mail.python.org/mailman/listinfo/image-sig
