Re: Pinholes in HIE

[Kayo Matsushita <kayo@xxxxxxxxxxxxx>]

At 18:24 -0400 9/12/96, John Sparks wrote:
>The ingredients are the same (acetic acid) except the Indicator version
>adds an indicator.
and...

At 23:19 -0400 9/12/96, Robert Long wrote:
>I believe that both include dilute acetic acid, no?  My impression was
>that the only essential difference was the presence of the color
>"indicator" that it triggered by the loss of acidity as the stop bath
>becomes exhausted.

Well, this is what I wasn't sure since Kodak doesn't disclose the
ingredients of indicator stop bath other than acetic acid. There are
various formulas for stop bath, and some formulas add sodium sulfate (which
prevents gelatine from swelling up) or sodium acetate (I don't know what
this one does) to acetic acid.   So, I thought it wouldn't be surprising if
Kodak had thrown in some chemicals that might make a difference in how
infrared films react to stop bath. I don't know...

BTW, I just learned that using a developer containing "sodium carbonate"
and acetic acid stop bath is known to cause this problem. I looked up
several photo books I had handy, and the only formula I found to contain it
was ABC Pyro listed in Ansel Adams' The Negative. I don't know if any
commercially available developer contains it, but anyone having this
problem might wanna check the developer's ingredients.


Kayo Matsushita - kayo@xxxxxxxxxxxxx -



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Topic No. 18