Thanks Leigh. I have never used Diafine and probably never will, so guess that doesn't apply to my
own experience or to typical developers.
Originally Posted by DREW WILEY
I believe the restriction applies to all two-part developers that rely on absorption of the first component into the emulsion.
You might consider Diafine for tray development. It's amazing because it's insensitive to variations in both time and temperature.
And it produces beautiful negatives. Probably better with slower films than fast ones (which I never use).
Leigh, I've never used Diaphine as they claim speed increases...this makes me nervous as I equate speed increasers as either more grain or inadequite shadow detail. But maybe I'm not such an old dog that I can't learn a new trick. I have used the Standard MH plate developer since 1948...and my grandfather used it since 1896! For 5X7"s, I mix up enough for 2 oz developer plus 4 oz water, and sloosh it across the film from the top quickly, then level the tray and agitate by tilting the tray for about 6 minutes. would this work with Diaphine?:whistling:
Originally Posted by Leigh B
I shoot Ilford FP4+ at 100 (box speed is 125) and have experienced no problems with tonality or grain. Superb results.
Originally Posted by premortho
Since Diafine has an almost infinite shelf life, and does not deplete with use in the traditional replenishment sense, I use
about a half gallon of liquid in a large 3 1/2" deep tray for developing 8x10.
Development uses straight stock solution, not diluted, which is returned to the storage bottle for re-use.
One caution... DO NOT pre-soak the film, regardless of any contrary instructions from the film manufacturer.
I normally develop six sheets at a time, emulsion down. It's a compensating developer, so minimal agitation.
I use four trays, one each for Solution A and Solution B, followed by regular indicator stop bath and rapid fix.
Wash, PermaWash, second wash, PhotoFlo, and dry as usual.
The critical thing about using Diafine is avoiding contamination. You should have a complete separate set of tray, graduates,
containers, and utensils for Solution A, and not use those for anything else. Even slight contamination will ruin it.
I really love Diafine for tray development because it's insensitive to time and temperature. As long as the temp is
70°F-85°F (not < 70) it's happy. Time is from 3 to 5 minutes in each solution, with no difference in results.
These features make it ideal for tray development IMO.
For the OP's questions . . . The comment in that thread he linked concerning Acros is, so far as I have ever read, bizarre.
The only film I've seen which developed with an accelerant was a graphic-arts lith-film for use in a large pre-print system (Agfa something??) and the material came in a cartridge affair. This was thirty years ago mind you. It looked to be that the developer was in the material then was activated by the liquid bath (perhaps similar to the rapid-access print proofing systems?), but all locked away inside the machine, giving a dry result in a minute or so. For a camera film? Never heard of it.
I know about EFKE and never did it.
I presoak everything, color and B&W, and use normal development in my Jobo.
Modern accelerants are generally polymers or are ballasted, and will not wash out of a film.
Ilford apparently uses a surfactant in their films which aids in development. I use a prewet anyhow. It works just fine. I am not aware of any accelerants that wash out of any film, but these surfactants can.
These polymers are compatible with gelatin and can be left in the film.
Since some of them act by creating greater swell and voids in the gelatin, even if they did wash out, their effect would remain due to the voids caused by their absence. But, since some of them are designed to attach to gelatin itself, they are not prone to washing out.
IDK how anyone here could "know" that a given product contains an accelerant as manufacturers do not announce these things.
PE - just out of curiosity what is your reason for presoaking everything? Is it because you do everything in the Jobo? Other than that, or when shuffling multiple sheets in a tray, I don't see what the point is otherwise (ie roll film in inversion tanks single sheets in trays etc). Since you know more about emulsions than anyone on here, it concerns me when you do something I don't!! :)
I use a Jobo, I use hard rubber tanks, and I use regular SS tanks for my films. I tray process plates.
I presoak everything to prevent unevenness and pinholes due to air bubbles.
On the issue of presoaking, I presoak 120 roll film for a couple of reasons. One is that, when the ambient temperature is very different from my target development temp, it allows me to adjust the temp inside the tank to something closer to what I want.
When it's 90F in the room, using a presoak of water in the low 60's prevents my developer temperature from immediately shooting up from 68 to somewhere in the 70's.