Donald, I just want to make sure we are clear, I said that it works best with the older formulation films such as Kodak Tri-X and Ilford HP5 not the newer T-grain like Delta and Tmax. I would not recommend using it on a slower films. Also if someone tries to get into B&W film developing at home, other than sending it to the lab, I would suggest something else than Diafine, just to get the hang of the process, D-76, Xtol or Ilford ID-11 are much more versatile and give you better look with all kind of films. Today we have so many options that people sometimes move to some hyped new formula, even though it has not been proven( I am looking at you Adox CMS), and marketing team is promising you nirvana.Diafine, as @vedmak noted, works best with cubic grain films, and ideally thicker emulsions -- because it depends on developing agent carried over in the gelatin from Bath A to do all the work when Bath B creates an alkaline environment; thinner emulsions will carry over less developer, and thus get less development. Diafine was a miracle in the 1960s. Today, you may find it doesn't work well, because even the "old technology" films of today are thin emulsions by the old standards.
That said, I've used it with Fomapan and early-2000s vintage Tri-X and generally got good results. Since it develops one way and one way only, you need to shoot some tests to determine what EI to use for your film in Diafine. I used to shoot Tri-X at EI 1200 (but the Tri-X we get now isn't the same as what I had in 2003), but Fomapan 400 was only good for EI 640 in Diafine.
I have a pair of bottles of Diafine that appear to be still good (after sitting in a shed for five years, and unused for seven before that) but I haven't tried them since getting my darkroom back in operation. I've been so happy with Xtol, I haven't worried about any other developer.
FWIW, Xtol is very temperature tolerant -- I routinely process at 16C because that's the temperature the air conditioning gives my darkroom. I expect that through the winter, I'll get the same excess from the heat, and wind up running my Xtol at 24C. I use a development timer app on my Android phone that compensates the time for actual temperature, and I find it works very well; my development has been very consistent just by way of compensating time for temperature.
What I'd recommend if you can't keep your chemicals cool in the summer is to use a diluted developer that gives times around 15 minutes, and then apply the 4% per degree F compensation rule. I've developed Tri-X and Fomapan at temperatures in the 30s (C) with Parodinal 1:50 and had no problems related to temperature -- I just calculated how much shorter to set the timer and went ahead. More recently, I've been using Xtol replenished stock at 16C (because that's been my darkroom temperature) and with compensated time, again, perfectly fine negatives.
If your chemicals are too warm, put .96 into your calculator and multiply by itself once for each extra degree F above 68, then multiply the result by the number of seconds in your intended time (for 7 minutes, Foma 400 in Xtol stock, that would be 420 seconds). Convert back to minutes and seconds, round to nearest 15 seconds if you like, set your timer, and pour. If your darkroom is too cool, make that 1.04 for the multiplication, same drill. I've got an app for my Android phone that acts as my development timer and automatically makes this calculation for me, but I've checked; its results are the same as I get with my old method -- and you can do this on a dime store 4-banger calculator, you don't need the HP-41C app I use for a calculator when I need it.
For some reason (Likely remembering things I've read or learned at some point incorrectly), I thought that developing at higher temps even with properly adjusted times impacted the contrast in a negative way? I don't remember the exact reason given but something about the faster reaction causing additional acceleration or I really don't remember. However I don't imagine you would suggest it if that was the case.
D-76 / ID-11 at 1:3 should give an unadjusted working time in the 20 minute range. That's something that if I run out I should be able to find at any camera shop that sells film as well. And I think the massive dev chart has a calculator that you put the new temps in and it will adjust the working time for you.
Freestyle has 1 gal Diafine in stock
As you say, D-76/ID-11, Xtol, etc. at highest dilutions are good choices for "too hot" conditions. High dilution Rodinal (equivalent) is another (and what I've used most in those conditions).
B&H has both quarts and gallons.
https://www.bhphotovideo.com/c/search?Ntt=diafine&N=0&InitialSearch=yes&sts=ma
Unfortunately, neither of those are available for purchase online, at least for me here in California - seems like in-store pick-up only. It might be one of those chemicals that B&H doesn't ship? The OP is in New York, but I think Buffalo is quite a ways from Manhattan.B&H has both quarts and gallons.
https://www.bhphotovideo.com/c/search?Ntt=diafine&N=0&InitialSearch=yes&sts=ma
Are you speaking metaphorically?I think Buffalo is quite a ways from Manhattan.
It is both.
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?