Archived from groups: comp.periphs.scanners,alt.comp.periphs.scanner (More info?
Never mind, I got my answer. NikonScan adjusts it's auto-exposure
settings according to the FULL frame, not to the crop window.
As I was scanning non-standard and "half-frame" transparencies,
light-leak from the sides affected negatively the auto-exposure. I
solved the problem by scanning an IT8 Q-60 target, then turning off
auto-exposure, thus, effectively locking it to a "normal/average" value
in order to scan my other non-standard frame size slides.
As for not being able to fill in completely the histogram, I also found
out that because the scanner scans at 14-bit, it cannot fill in a 16-bit
histogram. 1-bit of highlits and another bit of shadows goes to waste.
The solution is to 'stetch' the histogram values from 14 to 16-bit after
the scan. That makes sense to.
> When I scan slides, I always have to set 'Analog gain' to a positive
> value. I'm wondering if this is normal.