[sane-devel] how should you determine a good gamma correction to use through the backend?

[Karl Heinz Kremer]

On Feb 8, 2004, at 6:01 PM, Christopher Marshall wrote:
>
> Karl:
>
> Well, I suppose I was thinking of doing a scan with a correction of 0 
> (the default I believe),
> calculating a value of k, and using that value in further scans.
>
> Are you suggesting a iterative approach, where you start out 
> uncorrected (k=0), calculate k1, scan
> with k1, calculate k2, then scan with k2, and so on to a point of 
> diminishing returns?
>
> Chris Marshall
>

The default Gamma value is actually 1 (we are talking exponents). No, 
I'm not promoting an iterative approach. If you are using an ICC 
profile to correct your scan, you have to stick with the gamma value 
that was used to create the profile (you can of course create a number 
of profiles for a number of Gamma values. If you are not using ICC 
profiles, I would use the preview capabilities of the fontend to create 
a visually good scan, and then use e.g. Gimp to make it a perfect scan.

Karl Heinz