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Re: [Rollei] More OT Jobo advice



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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