Re: Enlarged Lith/Ortho negatives

William Laven (wmlaven@platinotype.com)
Mon, 29 Jun 1998 17:01:45 -0700 (PDT)

>After working with the APHS litho film/PYRO PMK for the past several days I
>have encountered a problem with pinholes on the final enlarged negatives.
>The interpositives, on FP4, are clean, but when I enlarge these onto the
>litho film (developed in PMK) there appear, as if out of the blue, numerous
>small clear pinholes on the negative. In places the pinholes are larger and
>the look is almost like that of the emulsion exploding. I am developing in
>ABS plastic tubes, using about 250ml of PMK per 8X10 sheet, at around 74F.
>
>Any ideas about what might be causing this problem?
>
>Sandy King

Sandy,

I've not worked with the APHS (yet) but know that some films, techpan being
the most notorious, can develop pin holes if an acidic stop bath is used.
With tech pan one just uses water to stop the development; it works fine
since the deveopers used are always compensating (ie weak) and stop fairly
handily with water alone. I wonder whether APHS also dislikes stop bath and
whether you might want to try water instead.

Bill

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