[filmscanners] Re: Grain aliasing: Thoughts, solutions?

["Tony Sleep" <TonySleep@halftone.co.uk>]

On Fri, 11 Oct 2002 19:28:39 -0700  George Hartzell
(hartzell@kestrel.alerce.com) wrote:

> I think that it can make a big difference between whether you degrade
> the frequency of the image before/while it's scanned (e.g. defocusing
> the scanner) or whether you try to blur in photoshop.
>
> When you do it as part of the scan, you just have to throw away enough
> information to get within the Nyquist limit.

Yes, I agree. Trying to deal with an aliased scan is far worse: the errors
are 0.5x the frequency of the optical signal which caused them,so much
larger. Moreover colour aliasing has introduced a whole new class of
problems which simply don't exist if you defocus/filter the optical image
upstream.

Regards

Tony Sleep - http://www.halftone.co.uk
Online portfolio & exhibit + film scanner info & comparisons
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