Development times for Russian mystery "A125" film

Question

On a recent trip to Russia I bought about a dozen canisters of B/W film I previously never heard about. FWIW, I bought them in two different stores in Moscow and St. Petersburg.

The guys at the store thankfully told me the development time for D76 and though the film seems to be the same: They call it "A125" and it is obviously bulk-loaded into repurposed film canisters, I got contradictory indications on the development times. D76 1+1 14 min in St P. and D76 1+1 12min in Moscow.

My Berlin lab of trust uses T-max RS and ideally I would like to get it developed there.

I currently don't have the possibility to develop it myself and seeing that I am not aware of a lab in Berlin that uses D76, I was wondering what my options are:

First: Does anyone have additional information about this stock of film?

Second: Does someone know development times for other developers, ideally T-max RS?

Lastly and most importantly, is there any way to deduce the development time, using the massive dev chart and using films with similar dev times in D76 as a reference?

Answer 1

First of all development times for B/W are just not that critical: you can get decent negs with fairly widely-varying times. Obviously if you want optimal & very repeatable negs you need to be significantly more careful. But you're not going to get that anyway if you buy random film, and actually some variation can be interesting sometimes.

That being said: look up a bunch of films in the massive dev chart and find their processing times with D-76 1+1. Especially look for ones with dev times around 10-15 minutes. Look up the same films' times for TMax-RS. Compute the ratios between the times: are they all approximately the same? If they're not, are the ones with D-76 times in the right ballpark approximately the same ratio? If they are use that factor, if not, look for films which have the same speed, and times between 10 & 15 minutes & repeat. Finally if there really is no common factor just guess something reasonable: chances are it will be fine.

Answer 2

D76 1:1 12 minutes 20°C normal agitation - to ISO 140 (low contrast). D76 1:1 15 minutes 20°C normal agitation - to ISO 150. HC110 dilution B 3 mins 10 sec to ISO 400

Answer 3

Since you have a dozen rolls... sacrifice one roll and use it to do some tests.

Have the lab clip sections of the roll and develop them at different times to see what time gives the best density.

Answer 4

One thing to recall with B&W films: for a given film speed and type (i.e. cubic grain or tabular grain), the development time will be about the same across most if not all manufacturers. That is, Ilford FP4+ and Fomapan 100 have a development time within half a minute of each other in most, if not all, developers (and half a minute out of six or seven minutes isn't very significant, especially with film you're unlikely to use again beyond those few rolls).

Thus, if you know the film speed (which is rather necessary if you're shooting it) and can be fairly confident it's traditional emulsion (cubic grain -- highly likely for Russian-made film, as it's probably Svema inside the cassettes, if not imported Adox or Foma), your lab really only needs to know "ISO 100/24 cubic grain emulsion" to get negatives that will look normal and print okay.