I have several rolls of Efke 100 & 50. I went looking for development times in D-76 1:1 at their rated ISOs. JandC lists a time of 12 minutes for 50 while Frugal Photographer and Digital Truth both list 8 minutes. For 100 JandC says 10, FP says 9 and DT says 9-12. Quite a spread. I'm just looking for a starting point here. Can somebody give me experience-based numbers for these films?
If it were me, I would plan on developing the film by inspection and begin inspecting the film at 85% of the lowest published time.
I can't speak for Efke 50 which I have yet to try, but the times given for Efke 25 on Frugal's chart appear to be accurate from my experience, if that is any help. I am very impressed with this film, by the way.
That is very helpful. JandC's time looked kind of off the chart.
While this doesn't directly answer Neal's question regarding Efke in D-76 I'll toss this into the pot...
Efke R100 (the 120 version) at EI 100. Late afternoon/early evening, mostly moderate lighting under clear skies. Some photos under open shade; others under open sky after sunset.
Neofin Blau, 30ml concentrate in 500ml distilled water (530ml total solution).
11:30 (eleven minutes, thirty seconds) @ 75°F.
Three inversions every minute in stainless reel/tank system.
I was aiming for a higher contrast index to suit both the lighting and my dichro head.
Lacking a densitometer I'll just say the results are very good. Excellent tonality with very satisfactory contrast for the lighting conditions (described above). Shadow detail was good but could be a bit better - this film in this developer might be better at EI 50-80.
As expected from Neofin acutance was high with grain that was sharp and very tight. This developer might be best with TMX, Pan F+ and Efke 25.
Efke R100 might be best with D-76/ID-11, Microdol-X, Perceptol, etc., if one wishes to minimize grain.
BTW, my Efke R100 negs curled up tighter than an angry rattlesnake. Never saw such ferociously curled negatives. Fortunately I use a glass carrier in my Durst M605 so there's no problem. Tension from the curl actually helps with positioning the negs in this usually fussy carrier - if you've used this type of carrier you know what I mean.
To further complicate things, I have been trying to standardize all my processing in a Jobo.
I shot a roll of R50 at 50 ISO, bracketed a stop each way and processed it at Frugal's suggested eight minutes, roughly compensating for the continuous agitation by cutting it to 6'30". The results weren't particularly conclusive by themselves but everything was nicely printable. This stuff lives up to it's reputation, it ain't no T-Max. More critical tests are required but I feel much more confident handling this film than when I made the original post in this thread.
I don't test with a densitometer either, I just tweak exposure and dev times until my average negs consistantly print the way I like them on a #2 paper and then call that "N". That way, I figure, it takes all my personal equipment, materials and method variables into account. I enjoy the technical aspects of photography but what goes on the wall is going to have to stand entirely on it's aesthetic and visual merits no matter what the numbers say.
If I manage to nail down some results that could possibly be useful to others, I'll be sure to post them.