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stradibarrius
18-Nov-2011, 13:14
If I use 1650mml/55.8ozs in a yankee tank as a dip tank, how many 4x5 sheets can I process before the chemistry is exhusted?
I normally use Rodinal 1+50, so that would be 33ml of Rodinal in 1650 ml of water @ 68deg.

DanK
18-Nov-2011, 14:01
If I use 1650mml/55.8ozs in a yankee tank as a dip tank, how many 4x5 sheets can I process before the chemistry is exhusted?
I normally use Rodinal 1+50, so that would be 33ml of Rodinal in 1650 ml of water @ 68deg.

I don't remember where it came from, but my notes show a minimum of 10ml Rodinal per 80sq/in of film...

Which would translate to 12 4x5 sheets (@33ml)- but also keep in mind it is a one shot developer once diluted - so really no matter how many sheets (up to 12) were put through it at one time, it would need to be tossed.

I've never used it beyond a one shot...

I'm sure someone will have the actual Agfa reference...

Thanks,
Dan

Brian C. Miller
18-Nov-2011, 14:20
Different developers have different capacities. Kodak Xtol has a very high capacity, but it can't be replenished. Other developers are simply replenishment developers, and were formulated for high-volume commercial work, and don't get "good" for at least a few days.

Jason Greenberg Motamedi
18-Nov-2011, 14:33
... Kodak Xtol has a very high capacity, but it can't be replenished...

Xtol can be reused and replenished when used in stock form. See Kodak Publication J-109 (http://www.kodak.com/global/en/professional/support/techPubs/j109/j109.pdf)

Bill Burk
18-Nov-2011, 18:58
As you develop additional sheets of film you should increase your development time, at least in D-76 I have found this to be true.

In my case I saw my CI drop like a rock over a series of three batches, which "would have" been compensated for by extending development time (as the data sheets say). But I just took away the lesson to always use fresh developer. I'd prefer to be able to predict my CI.

Leigh
18-Nov-2011, 22:48
I don't remember where it came from, but my notes show a minimum of 10ml Rodinal per 80sq/in of film...
That's correct per the Agfa Rodinal datasheet.

It says a minimum of 10ml of concentrate per 8x10 sheet or equivalent (1 36-exp roll of 35mm or 4 4x5 sheets or...).

Rodinal is definitely a one-shot developer. It deteriorates rapidly when exposed to air in its diluted form. It should be mixed just before use.

- Leigh

sergiob
29-Nov-2011, 18:39
I read somewhere you need 10ml for one 8x10 sheet.

polyglot
29-Nov-2011, 21:43
10mL per 8x10, 33 mL concentrate therefore 4*3.3 = 13 sheets of 4x5 if processed in a single batch.

If you process in several batches, the byproducts of development produced by the earlier batches will hinder development of the later batches. And (if you're agitating the chemistry properly so that it mixes), and using a lot less than 13 sheets in each batch, the developer will be more-active for the early batches due to lack of byproducts.

tl;dr: you use it just once or the results are quite variable.

If you're a tightwad and want to develop only about 6 sheets at a time but can't put any less than 1.65L in there to cover the film, then 1+100 or a different developer might be more appropriate. Replenishable developers solve this problem - doesn't matter how big your tank is as long as it's big enough and you replace only the developer that was exhausted.

Xtol is quite replenishable as stock solution.