Re: [APML] Scanning slides (Was IC 410 uploaded and IC 405 adjusted)

[Alan Voetsch <alanv12952@yahoo.com>]

Hey Stuart,

--- Stuart Heggie <stuart.j.heggie@sympatico.ca> wrote:
> emulsion that may be a factor is this: Each grain has to be hit by
> more than a certain number of
> photons or the chemical reaction reverses (so I'm told). This
> suggests that at sufficiently high
> f-ratio and hence exposure time, the number of photons hitting the
> grain in the emulsion is too few
> over any time frame to sustain the chemical reaction and so you are
> losing signal.

 I understand, but have never heard this. That doesn't mean it isn't
so. And if true, would explain a problem. Then again, others would also
have the same result, at least those who are using a similar setup.
Let's see.

To the film experts: can the chemical reaction reverse if not hit by 
enough photons?

Thanks,
Alan

 


=====
SCT Astrophotography: http://www.pbase.com/avoetsch/astrophotography
FS-102 G-11/Gemini: http://www.pbase.com/avoetsch12952/tak_fs102
& http://www.pbase.com/avoetsch12952/fs102


		
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