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Re: filmscanners: Vuescan - A few technical questions
IronWorks writes ...
> I never thought to try it. [long exposure pass] How does it benefit
the scan?
>
> I had assumed that the normal pass would gather sufficient
information,
> especially when it passes multiple times picking up missed or bad
data and
> then averaging them out.
VS's "long exposure pass" would in effect increase the exposure
time. Using a camera analogy, think of it as exposing for the shadows
and increasing the shutter time ... and then later blending this
exposure with an earlier frame exposed normally (... hence, likely
registration problems ...).
Now that I think about it, LEP isn't much different from multiple
passes, and the evidence seems to bear this out. I scanned an image
using LEP and 16x MP. After I saw the mis-registration for LEP, I
scanned again at 16x MP only. I couldn't see where LEP improved over
16x MP. After all (Ed may comment), what's the difference between
increasing the exposure time and scanning mutiple times?? I can
understand how exposing for shadows improves film response, ... but
digitally, we are only making numbers larger or averaging smaller
numbers ... both would seem to produce the same effect for dense areas
of film(?)
shAf :o)
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