[filmscanners] Re: Polaroid SS4000, noise, and oversampling (was: VueScan 7.5 beta

[TonySleep@halftone.co.uk]

On Fri, 08 Feb 2002 16:28:20 -0600  Eric (ericm@pobox.com) wrote:


> Why wouldn't oversampling and averaging help reduce hardware-caused
> noise?

It can be a pointless exercise. If the noise is down below the black point
of the image, you can just discard it by clipping the histogram. With
properly-exposed originals this is largely the case with the SS4000.

However if you want to increase shadow separation by editing the curve in
that region, or apply extreme gamma or contrast increases overall, you will
amplify the residual noise as well. In those circumstances multiscanning
might have something to offer.

Regards

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