Re: Problem with Wisner 4x5 camera probably solved!

[George L Smyth <GLSmyth@xxxxxxx>]

Jud Hofmann wrote:
>
> One mechanism that could do this fogging is flourescence:  when the dark
> slide was exposed to the visible and UV from the sun, it flouresces -
> emitting visible light.  In many materials, this emission continues for a
> short time after the light that caused it is removed.  When you turned the
> dark slide around to face the film, the flourescence fogged the film.

If this is the case, then wouldn't all film be fogged in the same
manner.  I would guess that the holder would then become useless for any
film.  I am assuming that the makers of film holders chose their
materials a bit more reasonably.

george

-- 
 Handmade Photographic Images     
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