When I first started in this great hobby (addiction?) all I had was a several years old half bottle of nice, brown Rodinal. Then I went on an experimenting spree, buying all the types of film I could get my handson (as in : "lets see what this does...hmm..). While, in retrospective, I have to say that some film/exposure combos left a little tobe desired under my by the book Rodinal development, all came out ranging from well to outstanding!!!(factor into that a beginner doing all the processing!).
I found that faster filmsin 1+25 do not come out as nicely detailed (I am not sure if this is the right term... but its the best I can think up right now) as they did in 1+50. Also, the times being longer gave me the luxury of knowing that a second this way or that would have so much less effect than in 1+25 mode.
As to the temperature, here is the biggest example of my "noobism": I have measured the temp of carefully adjusted tap water, and then the phone rang. I picked up, talked a bit, then came back to the running tap and DID NOT re-measre the temp. This occured to me halfway through developer, so I dunked the thermometer in the stop bath (filled at the same time) and had a 27 deg C temp!!! Guess what - it still worked decently well. I have also had the opposite happen - the temp dropped to 18*C... still worked (a little thinner than I expected, but quite sharp and good detail.
Looking at a classic film like a TriX or FP4+ (my new favorite!) though a grain magnifier under a condenser enlarger you feel like someone just punched your eyeball!!! I love it!!! And with Delta 100 and PanF, it seems to work quite well too, with very rich tones - I think because of the little fine grains getting really sharp in that image, yet being so tiny, there is really no grain to speak of (until you magnify it).
The biggest drawback I can see (and really its not a drawback, just a characteristic of hte developer) is that one stop is all you can really hope for as far as a noticeable push is required. After that, I find it makes very little difference (comperatively, of course).
Hope this helps, and please keep in mind that I am a relative beginner, and someof my experiences can be chalked up to lack there of!
Best of luck - love Rodinal and it will love you back - I guarantee it!
