Re: [APML] TP Pre Rinse

[George Anderson <georgea@cam.org>]

If you ran hypered and unhypered side by side during your test and the
hypered was trashed and the unhypered was fine I'd say the results are
pretty conclusive and match what Kent has been saying ever since I
suggested a few weeks back that a pre-soak would eliminate air bubbles.
Kent and others had warned of blotchiness (sp?), pinholes, and emulsion
lifting as well as an increase in fog.
Your test showed that there is a large difference between the best
processing methods for hypered versus unhypered film.
For your next test I'd suggest developing a hypered sheet without
pre-soak just in case hypered doesn't like the rotary processor.
My 0.02.

George Anderson
Montreal Canada

Clear skies and good health

Jim Janusz wrote:
> 
> Well for what it's worth I ran my test tonight.  I knew better but I
> actually tested two things at the same time, not good for scientific
> accuracy.  The two test parameters were the five minute water pre-rinse and
> a new Jobo 3010 expert rotary developing tank.
> 
> The test was to use the new tank and do all of the other steps as I normally
> do and add the pre-rinse.  I used one sheet of hypered and one sheet of
> un-hypered 4x5 TP.
> 
> Results were a disaster for the hypered sheet.  It was totally ruined with
> dark areas that look like the emulsion ran.  Maybe the water did this as it
> was introduced to the tank?  The direction of the flow is follows the
> upright tank position, not the horizontal rotary position.  Totally weird.
> The un-hypered sheet was perfect.
> 
> If it were not for the fact I used a new un-proven tank I would say that
> pre-soaking is still not the thing to do.  As Kent said below hypered film
> hates water.
> 
> At some point I will re-run the test but for now I need my hypered sheets
> for this weekend.
> 
> Keep your TP dry mates.........
> 
> 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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