Why Presoak?

[Mark Stahlke]

I've been shooting Ilford films - Delta 100, FP4+, HP5+ and processing them in Ilford DD-X. I've never done a presoak step when developing these films because Ilfrord recommends against it. They claim it can cause uneven development. I process 4x5 in a Combiplan tank and 8x10 in trays and I haven't seen any development problems with my negatives but I'm curious.

What is the purpose of soaking film in water prior to development? Why does Ilford suggest this could cause uneven development?

Thanks,
Mark

[Pawlowski6132]

I've been shooting Ilford films - Delta 100, FP4+, HP5+ and processing them in Ilford DD-X. I've never done a presoak step when developing these films because Ilfrord recommends against it. They claim it can cause uneven development. I process 4x5 in a Combiplan tank and 8x10 in trays and I haven't seen any development problems with my negatives but I'm curious.

What is the purpose of soaking film in water prior to development? Why does Ilford suggest this could cause uneven development?

Thanks,
Mark

Ironically, I presoak for a more even development.

[bobwysiwyg]

Likewise. I've read enough threads here on the pre-soak vs. not to come to the conclusion that it matters little either way, but it was the way I was taught longer ago than I care to think about. It's a bit like starting a "which oil is better?" on a motorcycle forum. :rolleyes:

[windpointphoto]

How about just trying both methods, see for yourself if there's any difference, and then you'll know. Make some exposures of different scenes, tones etc.

[Peter De Smidt]

Ilford puts wetting agents into the emulsion. A pre rinse can wash those out. I don't know how much difference that can make, but a pre-rinse is an extra and unnecessary step with Ilford BW films.

[Merg Ross]

For tray development of sheet film I have always used a presoak, regardless of film manufacturer; this includes the Ilford films that you mention. A presoak allows films to be placed in the tray very quickly, eliminating the chance that they might stick together. This assumes a time and temperature development procedure as opposed to developing by inspection. I most often develop twelve sheets at a time. In practice, a presoak increases development time slightly, although you will find comments to the contrary. For tank development such, as you mention, I see no advantage to a presoak.

Edit: Perhaps there is an advantage in that I have never had the problem of uneven development.

[Ed Richards]

I process Tmax in a Jobo Expert Drum. Kodak does not recommend a presoak, so I did not do it for the first few months. I saw occasional streaks and uneven development in clear skies. I started presoaking for 5 minutes and have not had the problem since. No other changes.

[Gem Singer]

What Merg said.

(I only use Ilford HP-5+ film).

[Ken Lee]

What Gem said.

[D. Bryant]

For tray development of sheet film I have always used a presoak, regardless of film manufacturer; this includes the Ilford films that you mention. A presoak allows films to be placed in the tray very quickly, eliminating the chance that they might stick together. This assumes a time and temperature development procedure as opposed to developing by inspection. I most often develop twelve sheets at a time. In practice, a presoak increases development time slightly, although you will find comments to the contrary. For tank development such, as you mention, I see no advantage to a presoak.

Edit: Perhaps there is an advantage in that I have never had the problem of uneven development.

+1!

What Merg said.

Film processed in BTZS tubes with pyro need a presoak. Ilford film never seemed to care.

Don Bryant

[DanK]

I dip and dunk sheet film and always pre-wet/pre-soak in plain water prior to development - but only for 60 seconds or so....

I was taught the pre-soak softens the anti-halation layer and/or super-coating allowing a more even development...so it has become ritual...

Although, I doubt I'd see a difference....I don't pre-wet/pre-soak roll films...

Dan

[coops]

I had some uneven development also with the Jobo, but sinse I started pre-soaking, no problems

[Gary L. Quay]

I've done it both ways, but I've never seen a difference.

I have heard, however, that when you use a pre-soak, allow 30 seconds extra development time for the developer to reach the emulsion.

--Gary

[Peter De Smidt]

So,

The reasons to pre-soak:
1) bring the emulsion up to temp.
2) get rid of air bubbles.
3) make handling easier, such as with tray processing.
4) lengthen the development time.
5) get dye out of emulsion (although I don't know why you'd want to do it.)
6) increase evenness of development with some films and processes.

The reasons not to do it:
1) It's an extra step.
2) It might lead to less even developing with some films/processes.
3) It lengthens development time.

Btw., all films/develop combos don't respond in the same way to a pre-rinse. I've heard of it actually increasing contrast, for example. The length of time is very important. Do it the same way each time. Jobo found that times much shorter than 5 minutes lead to variable results. The best way to tell if it helps for you is to try it in a controlled way. When I processed sheet film in trays, I used one. Since moving to a Jobo with and expert drum, I have not, at least with BW.

[jim kitchen]

Folks,

I pre-soak for six minutes, no more no less, whether I use Ilford films, Kodak films and, or a rotational device with both films, and I would surely tell you in heart-beat if pre-soaking affected my development process or not... :)

I have pre-soaked my film for more than thirty years, and I have yet to see any detriment to this issue. If Ilford, for example, says that you should not, and if you follow their recommendation, complete with a few staunch Ilford supporters emphatically stating that fact, then do it. I must tell you that pre-soaking my film is an important step within my film development process, and I would not recommend removing this step, period. My previous film development times that I published for TMY-2 did not state this fact, because I forgot to include that comment.

That said, it is your choice, your process, and your results that you should be concerned with, going forward. Experiment, and you will see whether it is an important step or not.

Just my two pennies...

jim k

[davemiller]

I pre-soak for five minutes as part of my temperature stabilisation process for both roll and sheet film.

[Brian Ellis]

Depends on how much you enjoy standing in a darkroom inhaling chemical fumes. If that's something you enjoy then presoak. If you don't enjoy that then don't presoak.

I've done it both ways and never noticed any difference at all. My impression is that presoaking used to be standard procedure with the old "thick emulsion" films because with those films it promoted even development (not sure where I read that or how true it is, it's just something I read somewhere some time). With today's films I don't think it serves any purpose and in some cases (e.g. Ilford films) may actually create problems though I presoaked HP5+ for a while when I was using pyro and never saw any problems. Basically I think it's a non-issue, do whatever you want to do, it isn't going to matter either way except in terms of how much time you spend in the darkroom.

[bob carnie]

One of the reasons for presoak is to swell the emulsion and make it able to accept the developer faster.
I use distilled water for my developers , because I believe the lack of minerals allow less resistance for the developer to get to the film.

I gleaned this from reading and re reading Gordon Hutchings writings.

I use rotary for the last 15 years and only presoak Pyro process, for D76 and others I do not presoak.

As well , even though I use rotary, I manually agitate for the first 20 seconds of any run. From a nasty bout of road ruts , that almost drove me insane and stopped all customer film production.

[wclavey]

I never used pre-soaking for 20+ years of MF film development until I started using Arista EDU branded FOMA film. I had terrible problems with air bells and used the pre-soak as a way to eliminate them. Then, when I started shooting 4x5, I noticed that if I included the pre-soak it eliminated the streaking problems I sometimes had in the sky (as someone described above). I use a Jobo tank and a Uniroller for all my film now, all formats, and I pre-soak for 4 minutes in 700ml of water with 7 drops of photoflow.

[Paul Metcalf]

Here's another take on presoaking for those that use Jobo print drums for 8x10 or larger film that spans one or more of the small ridges in the drum. There have been other posts in the past that have mentioned that when doing this they get lines on the film when using pyro/staining developers but the lines only show up when printed. Hence the belief that the ridges in the tank cause this. Speculation is that the ridges cause some sort of additional stress or such, maybe even a difference in the speed of the chemical flow over the bumps, in which either case effects the hardening of the film in that area. And from what I've been able to gather it seems as though those that have had this problem do not presoak.

MY speculation is that the film is in more direct contact with the tube at these ridges such that the film temp is different due to difference in heat transfer for some amount of the initial development, hence the different hardening and lines in the prints. I've never had the lines in my prints, and I presoak for 5 minutes, so I'm quessing that the overall film, even along the ridges, is at the same temp and thus recieves equal development and hardening. YMMV, and I could be full of it, which is ok, because I don't get lines in any case!

Westley - I would be concerned about chemical contamination with the photoflo prior to the developer unless it was rinsed well, but if you haven't had any problems, I guess it's not an issue.

[Ken Lee]

I use a Jobo tank and a Uniroller for all my film now, all formats, and I pre-soak for 4 minutes in 700ml of water with 7 drops of photoflow.

As a surfactant (http://en.wikipedia.org/wiki/Surfactant), won't Photo-Flo increase the formation of bubbles ?

Doesn't it also change the pH of the water, and thus influence the developer ?

[Nathan Potter]

As Bob Carnie mentioned, the presoak swells the emulsion due to the influx of water into the emulsion. A tiny bit of photoflo can aid this in the form of more uniformity. But the swelled and water soaked emulsion slows the initial influx of developer at that stage resulting in slightly longer development times to obtain the same negative density. With standard D76 and Tmax the increase in time is almost miniscule, less than 10% - seems to be about 5% in the only tests I've done by dip and dunk.

Nate Potter, Austin TX..

[RichardRitter]

I presoak for all of Peter De Smidt resons plus it take some time to get either 20 sheets of 4 x 5 or 12 sheets of 8 x 10 film into the tray.

[wclavey]

As a surfactant (http://en.wikipedia.org/wiki/Surfactant), won't Photo-Flo increase the formation of bubbles ?

Ken, sorry, been away a few days...

The bubbles that formed on the surface of the Arista.EDU film were very stubborn... rapping the tank or using the roller base did not dislodge all of them. I did a test in daylight where I put a section of film in the reel in the tank, ran the roller for 4 min and took the film out, and the bubbles were still there. Adding photoflow was a test and it did eliminate the bubbles on the surface.

I have speculated on other threads about this topic where I suggest that perhaps the bubble problems I had were a result of the combination of Arista.EDU film and the very hard water we have here in Houston. I will say that the bubbles were never a problem when I lived in CT, NY or PA.

[Scott Walker]

I started out tray develop[ing 4x5 without a pre soak and never ran into problems although I am only coordinated enough to do 6 sheets at a time. I used Kodak film almost exclusively though. I have now shifted to mostly 8x10 (still tray developed) and I noticed sporadic uneven development with both Kodak and Ilford films so I started using a 5 minute presoak and cured the problem. So now I have started doing a presoak with the 4x5 as well, mostly because it is less stressful when first immersing the film and trying to make sure none of the sheets stick together.

[Tom Kershaw]

The instructions for the Kodak Professional 5 litre single use kit specifically advise against a pre-soak due to potential for uneven development and developer function.

Tom

[iml]

I had problems with streaking and uneven development with 5x4 in a Combiplan tank, pretty much 1 sheet in every batch would have some problem. 5 mins presoaking has completely cured it, I've had no problems since, 100 sheets or so later.

[cyrus]

Presoaking sheet film prevents them from sticking to eachother in the developer. Trying to separate stuck film in development is a royal pain.

[Ken Lee]

That just may be the best answer so far.

It's bad enough trying to separate them when they're just sitting in water - but when the clock is ticking, it's not only a challenge, both negatives are often ruined due to uneven development.

[Andrew O'Neill]

I don't presoak anymore. I have noticed streaks when developing HP5 8x10 sheets on occasion when I did presoak. I use pyrocat-hd in BTZS.

[Ken Lee]

I used to take a 5-minute soak myself - once a month, whether I needed it or not.

Not any more :rolleyes:

[Andrew O'Neill]

I remember back in the day when a weekly bath was the norm...

[pergorm]

I presoak because it just isn't right pouring blue developer from the tank in the end, so the antihalation layer must go!! (ADOX CHS 50)

Per

[renes]

Question to Tri-x 320 and Plus-X users (roll film 120): do you pre-soak? If so, how long?

Does Kodak recommend pre-soaking with these classic emulsions?

[Brian Ellis]

That just may be the best answer so far.

It's bad enough trying to separate them when they're just sitting in water - but when the clock is ticking, it's not only a challenge, both negatives are often ruined due to uneven development.

Strange, I've never had that happen. Probably because I never try to insert a stack of film all at once in the developer. I slip the film in a sheet at a time, quickly. Takes only a few seconds so there's no effect on development times. Of course I don't do 12 sheets at a time either. Anyone who can do that without scratching and while keeping track of the N, the plus, and the minus sheets has my admiration and respect.