How long does working dilution Rodinal last

[TexasRancher]

Hello,
I've been using Rodinal, 1:50, to test some older films. I'm using 2000ml solution for only three of four sheets of 4x5. How long can I expect to get repeatable results out of Rodinal 1:50 in a covered tray? Do I need to mix it up every day?
charlie

 

[fotch]

4 4x5 sheets are equal to a roll of 120 or 36x 35mm. I would toss it.

 

[darkosaric]

Hi Charlie,

I would not use it the day after, not even after couple of hours. You can do your own testing, but better be safe than sorry. In all process 40ml or Rodinal is the cheapest part. You can maybe mix less than 2 liters of working solution?

 

[wildbill]

Why are you using so much developer?
500ml would be fine. Rodinal is probably the cheapsest developer available, use it one shot or immediately do a second run if you must.
Wasting developer? Check these out.

 

[Neil Souch]

Rodinal is essentially a one-shot developer and to obtain consistent results it should be used as such. It is also cheap as chips at 1:50 so don't get tempted to re-use it at a later date and risk screwing up some expensive film.

Neil.

 

[Rudeofus]

If you want some unscientific numbers: today I mixed Calbe R09 (a common Rodinal clone) in 1:25 ratio and measured pH right away, then again after an hour. In this short time frame, pH dropped from 12.05 down to 11.85, and I would expect reduced activity after such a pH drop. Different Rodinal versions may behave differently, but most likely not by all that much. And you can expect even stronger pH drops in more dilute setups (like the very popular 1:50 and 1:100).

 

[John Bragg]

Mix just before use, use immediately, then throw away. Foolproof !