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Re: filmscanners: Anti-Newton Rings powder
on 8/29/01 10:37 PM, SKID Photography at skid@bway.net wrote:
>
> LAURIE SOLOMON wrote:
>
>> They might also use an Anti-Newton Rings powder on the
>> glass between it and the subject being scanned.
>
> Sorry for my ignorance....What is 'Anti-Newton Rings powder'?
>
When you place two flat surfaces together, you get a form of banding known
as Newton Rings that represent the different transference of light between
the surfaces due to the pressure. Glass slides, and even enlarger glass has
been coated for years with a transparent substance that prevents flat/flat
contact, spacing the two flat surfaces just far enough apart to prevent the
pressure banding.
Jim Snyder
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