Film Pre-Soak before developing

[Douglas P. Theall]

another question. I got alot of response to my developing questions and 2/3's o f them said something about pre-soaking film prior to developing. I'm going to use my unicolor drum for now so my question is do I just fill the thing up with water and let it sit 3-4 minutes? Then I empty it out and develop normally. I a lso would like some info on how you use hypo on the film. Right now I use it on ly on my fiber paper prior to selinium toneing. Thanks again for all the great insights you have given me. Doug

[Erik Ryberg]

Doug,

Just put more or less the same amount of water in as you will be putting developer (say 500 ml for the 8x10 drum, a liter for the 11x14 drum) and run it on the motor base for four minutes. Pour it out and add the developer.

After the stop, pour in the fixer, same as with roll film.

Good luck.

[John Hicks]

Exactly what problem do you intend to solve by using a presoak? If you're not ha ving a problem, don't solve it.

Hypo...I guess what you're referring to is ordinary sodium thiosulfate fixer; fix for about three times the length of time it takes to clear the film, or with that fixer, probably about 5-10 mins for standard films and about 8-12 mins for T-Max and Delta.

Kodak recommends rapid fixer for T-Max; also Anchell & Troop speculate that T- grain films don't completely fix in sodium thiosulfate fixer.

If you use ammonium thiosulfate rapid fixer, give 3-6 mins.

After the fix always use an HCA; you can either use the store-bought stuff or mix your own. Film HCA is 20g sodium sulfite and 5g sodium bisulfite in a liter of water. Give 3-5 mins in the HCA, then wash for 20-30 mins.

[Brian Ellis]

I seem to recall reading here or elsewhere recently that some manufacturers recommend against a pre-soak (or at least that it's unnecessary with their films). I believe Ilford is one, at least with respect to the HP5+ and FP4+ films. I use HP5+ and used to soak for three minutes. After reading about Ilford's recommendation, I stopped doing it and haven't noticed any difference in my negatives. As someone else said, I wouldn't pre-soak unless it's designed to cure a problem. The usual reason to pre-soak is to promote even development. If you're not getting uneven development then I'd forget it.

[N Dhananjay]

As noted above, lots of folks (Ilford, Anchell & Troop) recommend against a prewet since most modern films have stuff incorporated to promote even wetting etc. Phil Davies reported some tests he had done where a prewet did influence development, but did so in different ways with different films. It increased contrast on some film- developer combinations while decreasing it on others. So, as suggested above, if it ain't broke, don't fix it. If you do want to try a prewet, you will need to test your film-developer combiation to see what the influence of a prewet is. Good luck, DJ.

[paul owen]

Doug I used to only pre-soak the film if I'm developing it in pyro or DiXactol. I find that by adding a small pinch of sodium metaborate to the water I get much more even development of my negatives.

[Mark_437]

Here's a method that uses the best of both worlds. I adapted it from something Fred Newman reported that he used at the Mammoth Workshop to try to eliminate uneven developing of big film. I use 12x20 FP4+ and HP5+ and (like Ilford states) they contain a surfactant (wetting agent) on the emulsion. I'm using D-76 1:1 and what I do is add water to the tray and agitate for 4 minutes, then add an equal amount of D-76 to the water and develop for the required time, thus giving me the 1:1 dilution but still incorporating the wetting agent in the solution.

The bottom line is that this method works better than anything else I've tried (although I haven't tried everything) and reliably gives VERY even development of large negatives, so I'm sticking with it. This should also work with other development schemes and other developers (i.e. add water and agitate then add developer at double your final working strength). Whether or not this is beneficial with non-Ilford films is an exercise left for the reader.

Good luck!

[William Marderness]

I called Ilford tech to ask if I should or should not use a pre-soak with their films in my Jobo drum. The tech said to use the pre-soak for more even development in a drum. I think the wetting agent is there to help if you don't pre-soak, but pre-soaking a film with a wetting agent is not a problem.

[William Marderness]

Ilford says in their literature that a pre-soak can lead to uneven development, and Jobo warns against a short pre-soak because of uneven development. It seems the film must be soaked long enough to evenly absorb the water. I tried soaking half of a negative longer than the other half, and I did get uneven development.