> However, there's one more thing to consider - all scanners
> compensate for non-uniform light sources by doing a
> "shading" correction. For instance, the light intensity at
> the edges of the scan is almost always at least 20% dimmer
> than at the center.
Even with the controllable light source of the Nikon? I would have guessed
that they compensated for that by boosting the LED output, or are they not
individually controllable? Do you know how many LEDs there are, per chance,
and what the organization is?
> It appears that the Nikon hardware/firmware uses the same
> CCD shading for each of the 10,000 CCD positions (the
> same value for 3 different pixels) instead of the more
> optimal 30,000 different shading values. This appears to
> be the cause of the banding.
These are questions. The CCD is actually three 10k element CCDs. Do they
use one for each color, or scan all three with one color, then switch LED
color (there are three sets of LEDs, one R one G, and one B...do you happen
to know how they are organized?) and scan three with the next color LED etc?
If you wouldn't mind sharing a little more detail, I'd appreciate it.
Great work, BTW!
