[sane-devel] Affordable film scanner

[Ulrich Deiters]

The Canon FS27XX scanners are cases where you need a large gamma
to obtain good results (2.0-2.5). Right now the backend collects
12-bit data and converts them to 8 bit with a 4096 byte gamma
table (or exports them as 16-bit data). This usually works well;
but I admit that there are situations where a few more bits of depth
would be welcome.

Even if your scanner has got exposure controls, the question remains
whether it scans with fixed settings and manipulates the raw
digital data, or whether it really adjusts the gain and zero of
the amplifiers. This is probably the point where some companies
try to save money; good analog circuitry is expensive.

Regards,

Ulrich Deiters