RE: [APML] OK, the film?

["Joseph O'Neil" <joneil@multiboard.com>]

>Yes, I would feel pretty sure in your case that the problem is not in the
>processing.  Could it be that PPF itself is just not as stable an emulsion
>as most others?  And therefore more sensitive to expiration dates, freezing,
>bad tarot cards or whatever?


         This is pure speculation - but could the problem be long term 
exposure to oxygen?  Here's why i say that.

         Kodak has - correction - had - some really nice, premium quality 
B&W printing papers for use in the (wet) darkroom.
         The problem with some of these papers is they have limited shelf 
life.  After a while, they "grey out", and by that I mean, you can never 
get good whites in that paper, unless it was fresh.  It always has this 
dull look to it if you have had the paper in your darkroiom for a year or more.
         Conversely, I have never encountered this problem with good papers 
form Ilford or Agfa.

         There was a lot of discussion about this one some other photo 
lists & newsgroup, and the consensus was the paper emulsion was reacting to 
the air, specifically oxygen.

         Of course 35mm PPF would be in those plastic contianers, pretty 
well airtight, no?   But then photo paper is stored in heavy black plastic 
bags, and while not nearly as airtight as those 35mm film contianers, still 
you have say 100 sheets fo paper pressed down tight on top of each other, 
and oxygen is still reacting with  the paper emulsion.

         So, makes me wonder if some of these colour films have similar 
qualities from Kodak?  Like the old Aesop fable of the straw that broke the 
camel's back, this in itself is not the answer, but possibly one of the 
"straws".
joe






http://www.oneilphoto.on.ca
http://www.multiboard.com/~joneil


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