Archived posting to the Leica Users Group, 2001/04/22

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Subject: RE: [Leica] Film Demise
From: "Austin Franklin" <darkroom@ix.netcom.com>
Date: Sun, 22 Apr 2001 08:58:51 -0400

> Austin Franklin wrote:
>
> "Since you have to sample (scan) at
> 'slightly more than' 2x the frequency you want to get, that would be ((1 x
> (.5 x 5080)) x (1.5 x (.5 x 5080))) or ~9M pixels."
>
> This is incorrect, you don't seem to understand when it's appropriate to
> invoke the Nyquist criterion. The correct pixel count is four times your
> figure.
>
> David Morton
> dmorton@journalist.co.uk

Sorry, but my statement is perfectly correct.  Having 25 years of digital
signal processing and both digital imaging and digital audio design and
development experience, I believe I understand this topic quite well.
Digital imaging IS sampling, and as such, basic sampling theory does apply.
If you want to understand why, I can try to explain it to you, or you can
try to find some web sites that explain this basic principle.