Diafine developing times and temps

Ok-- so I admit it... I love Diafine.

Other than being a magical 2 part goo however, I know nothing about it. I have developed perhaps a thousand rolls in it, and recently I came across info that started talking about how temperature would affect the contrast, and that a longer soak in Part A changed the characteristics of the development curve. OI... Is this information nit picking or has anyone else played with times and temps for it?

I usually do 3 to 3 1/2 with a couple shakes and bangs in each part, and I try to keep the temp about 70, but I have never systematically attempted to see what major differences would do.

Temperature notwithstanding, time shouldn't matter very much beyond reasonable minimums. You need to soak the film in part A long enough to fully absorb developing agents. If you don't, you won't get as much shadow detail. If you extend the time, you won't gain any benefit.

Part B actually develops the film by being the alkaline environment that the developing agents need to function. Again, you need to soak a certain length of time to fully exhaust the developing agents. If you don't soak long enough, you'll have incomplete development which will result in slightly tamed-down highlights (the developer tends to exhaust in these areas, anyway, so I imagine there would be little change) and underdeveloped shadows (reducing effective film speed).

Based on my incomplete knowledge of photoscience, I imagine you need a longer time in part B if you are using a cooler temperature, because developing agents generally work less efficiently at lower temperatures. A higher temperature should allow a shorter time in part B, but using the normal time shouldn't cause any harm within reason.

35mm film is built to be processed around 20 degrees so being in the 18-24 window (70 is 21) is where you ought to be wherever possible.

Your argument about Part A-Part B is the one I shot at the guy at work that tried to convince me of greater time in part A = greater detail in shadows.

this guy: http://figitalrevolution.com

seems to be systematically testing films in Diafine and seems to have got some interesting results.

Me- I am just going to trudge on with it as before. I do dump it sometimes when there are huge floaty bits in it rather than straining it as the guy says, but I can still get a hundred or so rolls to the gallon of the stuff and have never had a failure because of temperature.

I have used Diafine at 80 degrees with 90 degree wash water without any negative effects, other than the emlusion on some 4X5 peeled off. Before I made a water chiller I used Diafine as my summer time developer as my tap water in the summer runs about 90 degrees.

The concept is pretty simple.

You soak the film in Solution and the emulsions soaks up the reducer. How much it soaks up determines highlight density and final contrast. Most gelatin emulsions are capable of soaking up more reducer at higher temperatures than at lower temperatures, but all have a saturation point at any given temperature.

Then you transfer the film to Solution B, which is the activator. The film quickly develops highlight density, but then the reducer runs out in the highlights and no additional development takes place. Shadow density, however, continue to develop as the developer takes a long time to run out in the shadows.

I generally recommend slightly longer development times than what is recommended in Diafine instructions, say 4+4 at 72F rather than 3+3 at 72F.

You can vary the contrast a bit by shorter or longer soak times in Solution A. Shorter times give less contrast, longer times more contrast.

Sandy King

Jeff Searust said:

Ok-- so I admit it... I love Diafine.

Other than being a magical 2 part goo however, I know nothing about it. I have developed perhaps a thousand rolls in it, and recently I came across info that started talking about how temperature would affect the contrast, and that a longer soak in Part A changed the characteristics of the development curve. OI... Is this information nit picking or has anyone else played with times and temps for it?

I usually do 3 to 3 1/2 with a couple shakes and bangs in each part, and I try to keep the temp about 70, but I have never systematically attempted to see what major differences would do.

Click to expand...

Wes Clavey, come on down!!!!!!!!!!!!!!!!!!!!!

You could try varying the concentration of the "A" solution if you're looking to get more or less contrast out of a divided developer. I do this when using Cachet's AB 55 and it gives me a half-stop push. I've also noticed significantly more contrasty results with higher temperatures. If you choose to experiment with higher temp. make sure the exchange between solution A and B happens as quickly as possible so as to prevent mottling and streaking.

The pH of the A bath is somewhere round 8-8.5. Depends who's measuring it. I make it nearer to 8.
At pH of 8 some development will occur in bath A and there is a report somewhere here on APUG of stand development in bath A only. Something like 45 mins.
Don Qualls uses bath A diluted 1:50 with a normal bath B for controlling contrast in microfilms used for continuous tones (pictorial).
So there's more ways to use diafine than what it says on the box.
frotog - Thanks for the tip on cooler solutions - the water here ex-tap is 30C. I am often tempted to use it straight out of the cupboard but have never experimented below 20. Might be something to try next.
I have used borax as bath B to improve on the granularity the carbonate in the packet B gives. Can't say I saw a lot of difference.

Murray

OK, I'm dealing with the mists of memory here, so bear with me.

I seem to recall that Diafine doesn't respond well to cooler temperatures, and that 70F or 21C should be considered a minimum.

Or was it Acufine?

Or was it the mid-70s, because I was too young to really appreciate the 60s .

Matt

All of this is my own experience; YMMV and I won't feel bad if you don't like it, agree, etc...

I started using Diafine when I lived in Peru and had no access to electricity, regular running water, etc. It was a reliable developer to use in the field at relatively high temperatures (water temps at or above 80 F)... and I have basically used it as my standard developer since then. I have mostly just used it as directed on the packaging with the following modifications:

• I use a 4 min pre-soak in water with 4 drops of Photo-flo before I start development - - I know, the box says no pre-soak, but I didn't burst into flames when I tried it, and it solved the problem of very stubborn airbells on some films - - remember, YMMV
• I use 4 min in each solution rather than 3 min and I invert the tank 2-3 times gently every minute - - I get streaky processing if I do not invert.

Until recently, I did this the same for all film sizes (35mm, 120, 4x5, and X-ray). However, based on Sandy King's excellent work as published in View Camera, I have modified my process for 4x5 film and have gotten excellent, entirely reproducible results and it has become my new standard and I am testing it now for 120, as well:

• 4 min pre-soak as above, with Photo-flo
• 4 min in each solution (A & B) that has been diluted 50% with water
• Continuous agitation in all steps on a Uniroller base that reverses direction every 1.5 rotations
• Rinse with water & fix normally

I think that Sandy would see the influence of his testing here...

Perhaps because 90% of my shooting is here in TX and I think we have exceptionally high natural contrast, the above process has worked very well to help tame the contrast. I take at least 3 meter readings for most 4x5 shots and still worry when the maximum spread is too high, but the above process has really helped deal with it. On negatives from less contrasty days, I do have to print with higher contrast filters (often #4) where I would have otherwise liked a 2.5 or 3, but that is a small price to pay to be able to put all my film in the same Jobo tank and process it all together (Heresy!)

I have also begun cross-processing C-41 color film in Diafine with the above method... the jury is still out. I have several pages of negatives to both scan and print in the darkroom. I am also experimenting with further reduction in the concentration of Solution A (perhaps incorrectly) to see if I can reduce the grain in smaller neatives on some films (specifically Arista) when processed with continuous agitation... I'd like to be able to put a tall Nikor tank of 120 or 35mm reels on the roller base to process, rather than manually inverting, and not get the large grain that appears when I do that size film in Diafine with continuous agitation.

I keep my house very cool in the winter (around 60-65) and I don't run A/C in the summer much so it is around 80 or higher most of the time (I like spending less on Gas and Electricity) so my Diaifine is used anywhere from 60-85 degrees and I have never had any issues with it. I always work it the same way, presoak with tap water for 2-3 minutes with a few water changes, part A for 4 minutes inverting 2-3X at the start, at 1:30 and 3:00 and the doing the smae for part B.

The beauty of Diafine for me is that it is a standardized process, if you don't want to have a standardized process I think there are much better choices than Diafine to work with

eye_of_wally said:

I keep my house very cool in the winter (around 60-65) and I don't run A/C in the summer much so it is around 80 or higher most of the time (I like spending less on Gas and Electricity) so my Diaifine is used anywhere from 60-85 degrees and I have never had any issues with it. I always work it the same way, presoak with tap water for 2-3 minutes with a few water changes, part A for 4 minutes inverting 2-3X at the start, at 1:30 and 3:00 and the doing the smae for part B.

The beauty of Diafine for me is that it is a standardized process, if you don't want to have a standardized process I think there are much better choices than Diafine to work with

Click to expand...

I absolutely agree... it is 100% reproducible and I know what I can count on. You said it so well.

How about Diafine in a Jobo expert tank? After reading the great posts here I see no reason why it wouldn't work...thinking of trying Adox ASA 50 with Diafine in the Jobo as noted, probably at 73-75F. Would appreciate any comments with developing times as well.

Ed

Ed,

The times I gave in the article in View Camera were for rotary processing in tubes, not unlike what you would do in a Jobo expert tank. I am certain that Diafine would work fine in Jobo. Note that it is necessary to dilute the developer 1:1 with water to keep the same CI you would get with any specific film using intermittent agitation.

Adox is not one of the films I have tested with Diafine.

Sandy King

Mahler_one said:

How about Diafine in a Jobo expert tank? After reading the great posts here I see no reason why it wouldn't work...thinking of trying Adox ASA 50 with Diafine in the Jobo as noted, probably at 73-75F. Would appreciate any comments with developing times as well.

Ed

Click to expand...

Mahler_one said:

thinking of trying Adox ASA 50 with Diafine in the Jobo as noted, probably at 73-75F. Would appreciate any comments with developing times as well.

Ed

Click to expand...

I have found all the Efke/Adox films to work great with Diafine

Sandy: Just so I am sure I understand you. You suggest diluting solution A and solution B with equal parts of water before using in the Jobo? Can the solution be reused, and if so, any suggestions as to the number of sheets before discarding? I suppose one could simulate intermittent agitation by simply turning on the rotational motor at intervals in order to simulate hand agitation, correct? In that case, one would probably use the two solutions as mixed without diluting.

Thanks.

That is correct. If you use the solution full strength with continuous agitaton you will get more contrast than with intermittent agitation. I tried to adjust for time to equalize contrast, but that did not work. Diluting the developer 1:1 with water does work.

I am fairly certain that the diluted developer could be saved and used again, but I have not tested it. However, since Diafine is so inexpensive my inclination would be to re-use it again the same day, but then discard at the end of the day.

I don't think that just turning on and off the rotation would work, but you would be leaving part of the film out of the developer, would you not?


Sandy King

Mahler_one said:

Sandy: Just so I am sure I understand you. You suggest diluting solution A and solution B with equal parts of water before using in the Jobo? Can the solution be reused, and if so, any suggestions as to the number of sheets before discarding? I suppose one could simulate intermittent agitation by simply turning on the rotational motor at intervals in order to simulate hand agitation, correct? In that case, one would probably use the two solutions as mixed without diluting.

Thanks.

Click to expand...

Sorry for the delay in responding Sandy....with reference to the Jobo and intermittent agitation...I simply don't know about the film being out of the developer when rotation is stopped.

I have just mixed up a 1 quart solution of Diafine and was hoping that someone could post a recommended film speed for TriX, Tmax 100 and HP4. The can I have of Diafine is probably 20 years old but seemed to mix fine - but the film speed info did not include Tmax. Is there any difference in the processing of roll film versus sheet film?
Gord

uhhhh

gordrob said:

I have just mixed up a 1 quart solution of Diafine and was hoping that someone could post a recommended film speed for TriX, Tmax 100 and HP4. The can I have of Diafine is probably 20 years old but seemed to mix fine - but the film speed info did not include Tmax. Is there any difference in the processing of roll film versus sheet film?
Gord

Click to expand...

You sure thats Diafine and not Acufine? Diafine is 2 parts, and the whole theory is that it's the same 3 minutes in part A then 3 in part B for any film.

I think we do see that several people are using it a bit differently, and I may try the presoak sometime.

It is Diafine - one qt each of A and B. Information on the box recommends Tri X film speed at 1600 and I was wondering what film speeds were producing the best results in Diafine.
Gord

FWIW

I used to rate Tri-X at 1600 with Diafine but now rate it at 800 or even 400 in flat light. You won't blowout the highlights and you get much better shadow detail this way