Re: [APML] TP Pre Rinse

[KGKIRKLEY@aol.com]

In a message dated 4/8/02 4:17:10 PM, jjanusz@dc.rr.com writes:

>As one of the individuals that have had bad experiences with pre-rinsing
>TP
>
>I was surprised to find this on the Jobo web site.
>
>
>
>A five minute pre-rinse of any black and white film works with the developer
>
>to produce a negative with manageable contrast and good tonal range, using
>
>the manufacturer's recommended 'hand process' (intermittent agitation)
>
>times. To pre-rinse, put a quantity of process temperature water in the
>
>tank, equal to, or slightly greater than, the amount of developer. Allow
>
>this loaded tank to rotate on the processor for five minutes. At the end
>of
>
>that period, pour out the pre-rinse water, and pour in the developer.
>
>Pre-Rinse times shorter than five minutes may produce irregular development,
>
>and should be avoided.
>
>
>
>When I tried pre-rinsing TP I never went anywhere near 5 minutes.  I'm
>going
>
>to test a sheet of hypered 4x5 TP with a 5 minute pre-rinse and will let
>you
>
>know the results.
>
>
>
>Jim

Jim:
The problem with doing a pre-soak with hypered Tech Pan goes back to the fact 
that hypered TP and moisture/water don't mix; ie. moisture causes increase in 
base fog level and possible unevenness. This can happen during 
transportation, storage, in the camera or in a pre-soak. That's why we use N2 
purges, etc.

I tried pre-soaking hypered TP 120 a few years back and the results were 
terrible.

Kent Kirkley 

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