Pre-soaking negsgreenspun.com : LUSENET : Large format photography : One Thread
I've never done a water pre soak before developing. I read it is so the negatives will "soak" in the developer. Is it better? I'd try it myself if I just could get those dang film hangers that are on back order from Calumet. Call me whatever you want, I'll never give up the "darkroom".
-- Raven (firstname.lastname@example.org), September 04, 2000
Sorry. I tried to erase that last sentence. I just don't want to be looked at as a "dinasour". I don't want to feel ancient or out dated for doing my craft the traditional way. Whatever draws me to use a view camera, also does so with the traditional darkroom. I think this style of printing is a craft to be appreciated, just like the appreciation we give to the view camera. A medium format camera would make life a lot easier, but I choose to lug that awsome piece of 4x5 equipment around instead. Is it that I'm not evolving, and my darkroom will be near impossible to use at some point in my lifetime. Gee, I hope not.
-- Raven (email@example.com), September 04, 2000.
I always did pre-soak my large-format negatives, the reason being that due to the large surface the negatives might streak and soaking makes the gelatine more receptive to the developer, at least , that's what I got told and I've never questioned the good results. I think that you are right to do so and I am interested in the answers too! About the cameras and the darkroom. This is precisely what I meant while answering somewhere else on the forum a entry which question the traditional darkroom to favour the digital one. I mean it is a contradiction to use a view camera and the do your printing on digital. I would be like to play medieval music on a sinthesizer which had been sampling the sound of the original instuments. The result can be interesting but the point is missed. regards
-- andrea milano (firstname.lastname@example.org), September 05, 2000.
I generally pre-soak for about a minute when using T-max emulsions. I get consistently good results. One thing you might consider if you are using the Ilford Delta films is that they incorporate a built-in wetting agent that Ilford says eliminates the need for pre-soak. If you do pre-soak those films, you will alter your development time, or so I am led to believe!
-- Robert A. Zeichner (email@example.com), September 05, 2000.
If you are pre-soaking, per JOBO tech types, TMax films do best with a 5 minute soak and the other films do well with about 2 minutes. If what you are doing works well, why change it? If you are starting out, try some using a pre-soak and some without and see if one gives any advantage over the other. If there is no actual advantage you can see, then you can go without the pre-soak.
-- Dan Smith (firstname.lastname@example.org), September 05, 2000.
Raven I always presoak both roll and sheet films for about 30 secs. to 1 min. The one time I didn't I got "air bells" and uneven development. Also this helps to bring the dev. tank to the same temp. as the developer solution. Regards, Trevor MONO-CRONE dinasour
-- Trevor Crone (email@example.com), September 05, 2000.
I've read that pre-soaking film, regardless of the manufacturer will cause a change in the development time due to the fact that the water in the emulsion must be "replaced" by developer, and that can take up to one minute to happen.
-- William Levitt (firstname.lastname@example.org), September 05, 2000.
Yes, pre-soaking can and most likely will change your development time a bit. But if you are a careful and observant worker you will do a basic test or two & find the times that work for you and how you photograph. The basic times are only a starting point. Many I know who follow them never realize the full potential of their negatives as they live with over or underdevelopment and don't know the difference. A small bit of time testing can save you years of mediocre images. Also, don't be afraid of longer development times, well past 10-15 minutes, if they give you the results you are looking and hoping for.
-- Dan Smith (email@example.com), September 05, 2000.
As one who is getting close to pre-dating the dinosaur age, I have been presoak negs for about 40 years because the man who taught me to develop film said to. I have never found a reason not to. I believe it makes the developer even out. I also never have air bubbles and I have solved the air bubble problem for a lot of younger photographers by suggesting a pre-soak. I usually add a bit more time to the development to allow time for the developer to replace the water. Some films, such as the old Plus-X emulsion, almost required a water soak to prevent bubbles. The way I feel about it, it takes just a minute or two, so why not do it for insurance. I manage to do about every thing else to negs that can be done to damage them, but I never have an air bubble.
-- Doug Paramore (firstname.lastname@example.org), September 05, 2000.
Very short presoaks should be avoided. If the water does not have a chance to soak the film evenly, it may cause uneven development. I have tested the difference between presoaked and non-presoaked negatives. I had to add about 15% to the development time with the presoaked negatives to get similar densities.
-- William Marderness (email@example.com), September 05, 2000.
I am a pre-soaker...in addition to all the other reasons given, I feel it allows me to get the sheets organized and ready to slide into the tray of developer... -Dave
-- Dave Richhart (firstname.lastname@example.org), September 05, 2000.
I presoak everything for 5 minutes. What's wrong with being a dinasour? Regards, Pat
-- pat krentz (email@example.com), September 05, 2000.
Thanks everybody for the response. What is wrong with being a dinasour???
-- Raven (firstname.lastname@example.org), September 06, 2000.
I process sheet film in trays and presoak not only to promote even development but to keep the damn film from sticking together-J
-- josh (email@example.com), September 07, 2000.
I believe the previous poster who mentioned "wetting agents" was correct - Ilford (and maybe others?) incorporate a wetting agent with their films. A way to pre-soak these films and not lose the benefits of the surfactant is to use the pre-soak water in the developer. While developing large film (12x20) in a tray, I do this by using a tip I got from Fred Newman (of Darkroom Innovations - now called The View Camera Store). I'm using D-76 at 1:1, and start by pre-soaking the film in 16 oz. of water (at normal dev. temp) for 4 min., then adding 16 oz. of D-76 directly to the water (giving me a dilution of 1:1) and starting the development timer at that point. It works great - smooth skies, no streaking of any kind, etc. I don't see why this method couldn't also be used in rotary tanks.
-- Mark Parsons (Polar@thegrid.net), September 08, 2000.
I don't think anyone who frequents a "Large Format Photography" page would consider you a dinosaur for not wanting to give up silver based photography and darkroom work.
The only times I can recall getting airbells (air bubbles) on my negatives was when I didn't presoak, so I do it all the time, unless the process forbids it (like 2 bath development, where airbells are unlikely, anyhow).
I frequently do 2. I am sure this changes the development rate, but I've never had uneven development with it. It just changes the total time I need. A very short presoak is likely to give you uneven absorbtion of the water and uneven development. One to 3 minutes should prevent this, as it has for me.
-- Charlie Strack (firstname.lastname@example.org), October 13, 2000.
I recently decided to switch to rotary processing for my negatives. I decided to use the Jobo 2500 series tank for 120 and 4x5 negs. I was having nothing but trouble until I discovered that the 5 minute prewet suggested by Jobo was the problem. I just completed a test of Agfa APX 100 in 120 size, developed in POTA. I found that the prewet seiously distorts the characteristic curve, causing an increase in density at the higher densities, thus increasing the overall contrast by quite a bit. The curves with and without prewet fall on top of each other up to a density of about 0.4. After that, the prewet causes a growth of density which reaches 0.3 or so, and has the effect of producing a very peculiar curve shape. Without the prewet, the curve runs smooth and straight as can be. Of course, I have not tested every film and developer, but my belief is that the 5-minute prewet should be viewed with deep suspicion. I will be keeping you posted on my website www.vsta.com/~alrob on further research in this area.
-- Al Robinson (email@example.com), November 22, 2000.