RE: Dimples on camera back

["George L Smyth" <GLSmyth@xxxxxxx>]

> -----Original Message-----
> From: owner-infrared@xxxxx [mailto:owner-infrared@xxxxx]On Behalf Of
> Mike Perkowitz
> Sent: Friday, October 29, 1999 4:22 PM
> To: infrared@xxxxx
> Subject: Re: Dimples on camera back
>
> could someone repeat what the problem is? :)

HIE does not have an antihalation layer.  So the radiation goes through the
film, strikes the pressure plate, and goes back through the film, reexposing
it.  This is the reason for the wonderful "halo" effect that some people
think has to do with heat.

The dimpled pressure plates of some camera direct the light back in such a
manner that the dimples are seen on the negative.

george

---
Handmade Photographic Images
http://www2.ari.net/glsmyth/

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