Re: [APML] Scanning a photo twice

[Philip Perkins <philip@astrocruise.com>]

Nicola, I have used a variation of this technique for some time for 
reducing scanner artefacts. The best technique however, is to scan 
normally, then scan again with the slide / negative rotated 180 degrees 
(upside down).  Then, in Photoshop, rotate the second scan back to normal 
and register the two images using Registar.  This is effective because most 
scanner artefacts are bars, lines, or fading that appear in the same part 
of the image but offset from centre - thus averaging normal and inverted 
scan helps to cancel such artefacts.  This is especially effective with 
thin negatives. It won't reduce graininess of course, and I have not found 
scanner noise to be an issue with the Polaroid scanners. You may want to see:
http://www.astrocruise.com/noisart.htm

--Philip


At 14:57 06/02/03 +0100, you wrote:
>Dear All,
>
>I was wondering if I can reduce a possible scanning noise or photo paper grain
>noise by scanning the photo twice in a different position over scanner's
>flatbed, and than to average the pictures on photoshop.
>
>What do you think about it?
>
>Cheers,
>Nicola


Philip Perkins - philip@astrocruise.com
Wiltshire UK & Luberon France
Astrocruise - http://www.astrocruise.com

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