Re: filmscanners: Supra 400 shadows

[John Matturri <jmatturr@earthlink.net>]

> > I have the exact same problem with Supra 400 - red and green speckles in
> > the shadows.  Like you, I can't get them to disappear without blowing
> > away a lot of shadow detail.  I don't know if a drum scan would solve
> > this or not - I've seen the same problem on both my SS4000 and my new
> > LS-4000, so I have my doubts.
>
> This is likely to be grain aliasing. Where exposure is slight, there aren't
> many dye clouds (grains), and if they are of a size to alias individual
> pixels or small groups, false colour is the outcome.
>
> Regards
>
> Tony Sleep
>

This is what my hunch was. I at first thought that the fact that the
problem also exists when the scan is 2000 dpi counted against that
theory, but given the ccd size is the same at both settings I think that
that doesn't hold up. Ed Hamrick asked me to send a raw scan but if it
is grain aliasing I'm not sure that there will be much that can be done
in software. On the other hand, if push comes to shove I would think
that a higher resolution drum scan would resolve the grain and solve the
problem (unfortunately at a monetary cost).

John M.