Re: Vuescan vs. Nikon Scan (was: filmscanners: Vuescan question)

[Rodrigo Amestica <ramestic@eso.org>]

Hi, related with the analog gains I would appreciate any enlightenment
about the following:

(my system is an LS2000+NikonScan 3.1)

1. after getting a preview, why does the GREEN histogram change when I
modify the RED gain (after pressing "redraw")? Before even buying an
scanner I always thought that there were some granted basic facts, like
that the three light sources are independent of each other. Under this
conditions gets difficult to tune each channel histogram independently
(I do not care about color balance, I'm trying to understand how
NikonScan drives the hardware underneath).

2. is the selected cropping area of the preview used to compute anything
before the final scanning? In NikonScan at least the preview histograms
reflects changes in the cropping area, but I'm not sure about the final
scan.

3. does VueScan behaves the same way as NikonScan in relation with
points 1 and 2 above?

Thanks in advance,
Rodrigo 
 
Ralf Schmode wrote:
> 
> 4. Learn about the "analog gain" feature that directly impacts on the
> scanner LED brightness, and its effect on the histogram. Try out how to 
>"center"
> the histogram of under- or overexposed images via this control.
>