bernhardmangelsgmxde
Two questions from a newbie:
1. How long does fixer actually last? Manufacturers say somewhere between 3 and 12 weeks. I’m currently using 3 litres at the same time... so that’s enough for 18 rolls of film (based on one litre of film fixer) and... plenty for PE paper... so significantly more than I, as a weekend snapper (and not even every weekend), use in 3 weeks. More than I need in 12 weeks, too. I’ve just been using the stuff until I considered it used up (calculated by square metres), and if that took a year... do I now have to expect my photos/films to go off in the near future?
2. I live on the 4th floor under the roof. I also have my darkroom there (=toilet). In summer it gets... quite warm in there. So far I’ve just carried on as if nothing were wrong, and made my prints even at 29°C. In N113. I actually find the results quite OK, i.e. no worse than in winter (with the Duka lamp and my presence in the bathroom, it does heat up to about 18°...)
Is N113 particularly insensitive to temperature? The data sheets often say: ‘Processing should take place at 20°’, don’t they?
I’d like to switch to E102 (I don’t have a big problem with preparing developer with powder, but if it can be avoided...) Does it behave similarly at those temperatures? And: How long does it actually last (roughly speaking?) I mean the working solution or the concentrate? (I’ve heard it lasts ‘a long time’, but what does that mean in days?)
Many thanks for your replies,
Best regards,
Bernhard
MirkoBoeddecker
Hello Bernhard,
The 12-week shelf life for the fixer is certainly a very conservative estimate. But I wouldn’t leave a batch standing for a whole year either, at least not if it’s already partly used up.
As for the 20 degrees, that’s actually specified as the standard for all the other figures that follow. So any other figures you find in your data sheet for the product in question (provided there’s no degree Celsius symbol after them ;-) apply to 20 degrees.
In principle, the chemistry works fine at 29 degrees and above, but your development or fixing times would be shorter.
And you should bear this reduction in mind, as over-fixing isn’t great either (keyword: washing or even bleaching) and neither is over-developing (keyword: base fog).
So if you bear this in mind and, for example, reduce your times by 30–40% at 24 degrees (or even 50–60% at 28 degrees) or extend them by 20% at 18 degrees, whilst keeping everything else constant, then you’ll no longer have any issues with fluctuating temperatures.
Best regards,
Mirko
