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Re: [Rollei] More OT Jobo advice
- Subject: Re: [Rollei] More OT Jobo advice
- From: Paul Kollas <pkkollas >
- Date: Tue, 6 May 2003 10:31:10 -0700
- References:
On Monday, May 5, 2003, at 05:25 PM, David Seifert wrote:
> Temperature control +/- .2 degree vs. .1 degree (matters for C-41
> color)
Just a comment-- I don't know of any commonly available thermometers
that indicate 0.1 degree gradations. My JOBO thermometer is calibrated
in 0.2, and is at least 1.0 degree off from my Paterson, Kodak, or
Frigidaire mercury thermometers. So verifying the accuracy of temp
control is an exercise in frustration. C-41 development time is
commonly 3m 15sec, so rigid temp control doesn't have much meaning for
single processing runs. Although, it definitely is desireable on
day-to-day or week-to-week turn-off/ turn-on repeatability. I'm just a
little skeptical that such tight tolerance is actually achieved in
these machines. And I'm also skeptical of the dire warnings about the
need for such tight control. Nice to have maybe, for critical
commercial work, but for run of the mill amateur happiness, "no
worries, mate". I try to keep within 0.5 degree, so don't try to pin
that 2 or 3 degree slop on me :-)
pk
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