Do you Pre-wash your film?

Do you Pre-wash your film?

  • Yes

    Votes: 233 42.5%

  • No

    Votes: 261 47.6%

  • What's a pre-wash?

    Votes: 54 9.9%
  • Total voters
    548
Reading answers does not compare to trying it.
Try it and if it works adopt it to your development process. It is a fact that things usually work differently for different cases, e.g. hard/soft water, long expired films, short long development and many more. Also, a fact is that presoaking (not-prewashing, you are not washing anything!) does not harm the whole process.
 
I don't know why you'd want to complicate a process with steps not recommended by the maker. And pre-washing generally is no option that is mentioned in the instructions, sometimes it is explicitly not recommended. In the rare cases where the instructions permit it, it is generally limited to some special condition like non-standard temperatures or concentrations. The few processes I've encountered where it is a explicit part were things few amateurs have ever tried at home...
 
rjbuzzclick said:
I pre-wash Fomapan film in 4x5 when drum developing. I was having an issue with pinholes in the emulsion (I already use water instead of a stop bath) and pre-washing seems to have mitigated the problem.
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Foma had quality problems with MF films and dust creating pin holes in the emulsion.

Long time ago, I was doing business with Foma USA, and Misha got stuck with a lot of MF film that was unusable due to pin hole problems. I tossed / gave away all my MF Foma film.

Misha was at the factory many times, and noted carelessness in the MF production line.

The 35mm 200 speed, sold under a number of names, was / is a terrific film.

Regards, John
 
Roger Hicks said:
My most recent post before this was over a year ago. I don't know why this is now appearing as a "recent post" but I've seen the same problem before, with my own posts and others. There has to be something wrong with the program.

Cheers,

R.
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Always good to hear from an old friend, I just dialed in today, had some issues to attend to.

Hope you still have some good wine down there, keep a cork screw or two in the lab?


Will be seeing Jorge with some luck this winter, missed last winter with the issues-- am patched up, well, almost.

John
 
Roger Hicks said:
My most recent post before this was over a year ago. I don't know why this is now appearing as a "recent post" but I've seen the same problem before, with my own posts and others. There has to be something wrong with the program.

Cheers,

R.
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When there is a new voter, then the thread appears on the home page list.

VB views all thread activity as "new."

As the old saying goes, it is not a bug, it is a feature.
 
Well, it's a necro-thread, but since it's here and so am I, I'll just repeat what I believe six or seven other people said in years past on this thread...

I do not pre-soak because I use Diafine. Diafine part A is supposed to 'soak into' the emulsion, which it cannot do if you have pre-soaked the film already. The directions say not to do it, I am smart enough to believe those directions.

I do recall a thread quite some time ago about Diafine and presoaking, a newbie wanted to know if he should presoak, he was urged not to, he did it anyway, and he ruined his roll of film. Oh well. Some people have to touch the paint, no matter what the sign says.
 
I learnt that way from day one and have done so ever since. Just makes sense to me. I typically dev either Kodak or Ilford B+W films and just use room temp tap water for a few minutes before each development session.

Not too strict with exact times, once the reels are in the tank, I run the water through them whilst I get everything else ready to start. Three to five minutes I guess.

Works well for me I feel.
 
Roger Hicks said:
Or, far more likely, it washes a dye out of it -- a dye that has already done its work during exposure...

Also, are you actually developing to ISO contrast and speed? It sounds more like you're relying on exposure indices (EIs). This is a good idea -- but it's a bad idea to confuse ISO and EI.

Cheers,

R.
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yea, the dye washes out.

Well I look at the test roll on a light box (daylight corrected), and use the negative that has the best contrast DR... and the ISO used for that negative (from my test notes) is my normal ISO.
 
DNG said:
yea, the dye washes out.

Well I look at the test roll on a light box (daylight corrected), and use the negative that has the best contrast DR... and the ISO used for that negative (from my test notes) is my normal ISO.
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Well, your normal EI, anyway. You can't have more than one ISO on a roll of film -- and you may not have any ISO at all, unless you're developing to ISO contrast standards.

Cheers,

R.
 
Roger Hicks said:
Well, your normal EI, anyway. You can't have more than one ISO on a roll of film -- and you may not have any ISO at all, unless you're developing to ISO contrast standards.

Cheers,

R.
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Okay I'm not doing a densitometer test here at different ISO. I am exposing a test roll from low film speeds, how high film speeds. in normal picture taking situations.

Then I am processing the film according to the box speed recommendation of my master developer chart software for developing film. I am then looking at the roll of film that does have different film speeds on the roll and determining which one has the best dynamic range, which includes looking at the contrast.

Then that film speed becomes my normal film speed for that particular developer and dilution and agitation. That has to do with my developing environment my temperatures my water, things of that nature. So that I get consistent results regardless of what the box speed recommendation is.

In other words, I don't give a hoot what the box speed says when I first use a roll of film that I have not used before. I will give that roll the test as I described above, and that test will determine for me in my film speed value that I will use to get the quality of negative that I want.

Typically, it is the boxed film speed. But maybe the contrast is a little too light from what I'd like. Therefore I would increase my developing time a little bit and change my agitation routine a little bit. Increasing my developing time by 15% or so so will give a nice little contrast boost. Better than increasing the agitation rate will.

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Pre-soaking is a technique I learned from the Ansel Adams books, I believe, though it could have been Fred Picker, who came out of the same "fine print" tradition. Another technique was to reduce agitatation. That comes from the fact that the developer is exhausted faster in highlight areas and works longer in the shadow areas bringing them out more. Check out the Ansel Adams books and the writings of Fred Picker and you will find all kinds of techniques that really do work. Thing like pre-exposure to decrease contrast in high contrast dappled sunlit scenes.
 
DNG said:
Okay I'm not doing a densitometer test here at different ISO. I am exposing a test roll from low film speeds, how high film speeds. in normal picture taking situations.

Then I am processing the film according to the box speed recommendation of my master developer chart software for developing film. I am then looking at the roll of film that does have different film speeds on the roll and determining which one has the best dynamic range, which includes looking at the contrast.

Then that film speed becomes my normal film speed for that particular developer and dilution and agitation. That has to do with my developing environment my temperatures my water, things of that nature. So that I get consistent results regardless of what the box speed recommendation is.

In other words, I don't give a hoot what the box speed says when I first use a roll of film that I have not used before. I will give that roll the test as I described above, and that test will determine for me in my film speed value that I will use to get the quality of negative that I want.

Typically, it is the boxed film speed. But maybe the contrast is a little too light from what I'd like. Therefore I would increase my developing time a little bit and change my agitation routine a little bit. Increasing my developing time by 15% or so so will give a nice little contrast boost. Better than increasing the agitation rate will.

Send from my Galaxy S5 using Tapatalk
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Sure. All I'm pointing out is that you are are using EIs (exposure indices) -- the exposures that work best for you. Even when your favourite EI and the box (ISO) speed are the same number, you may not be developing to ISO standards. It's just a little bee in my bonnet that I have about distinguishing EI and ISO, because they are not the same thing.

ISO speeds are a great starting point, as they ensure that film speeds are set scientifically rather than by the marketing department. Your approach, determining your own EI, is what all film manufacturers recommend. As you say, very often it is the box speed -- but all too often you get people saying that films aren't "really" as fast as their ISO speeds. You're not doing that, obviously, but it's why I generally take people to task over EI and ISO.

I completely agree that a 15% increase in dev. time is likely to give much more obvious (and useful) results than increased agitation: the importance of increased agitation is often grossly overrated.

Cheers,

R.
 
Water Thrice!

Water Thrice!

Prewet to bring film to developer temperature for more consistent temperatures and removes anti-halation layer.

Second wash is after developer, using two water washes to stop development. No stinky acetic acid stop bath (don't need citric acid either).

Third,after fixiing with RAPID fixer (ammonium thiosulfate only) give final water rinses, just three since rapid fixer clears very fast.
All water is from 5 liter pitcher, in which the film canister is immersed between agitations. Temp does not vary by more than fraction of degree over development times.
Denton
 
I have not read the complete thread, but just to add this perspective if not previously mentioned: Anybody using one of the automatic Jobos is pre-wetting because that's how the machines were programmed. At the time Jobo was at its height, the company recommended a pre-wet for rotary processing because it almost exactly compensated for the more aggressive agitation in rotary machines, versus traditional inversion processing. Thus, the company didn't have to go to the trouble of testing every film/developer combination on the planet all over again.
 
Denton said:
Prewet to bring film to developer temperature for more consistent temperatures and removes anti-halation layer.

Second wash is after developer, using two water washes to stop development. No stinky acetic acid stop bath (don't need citric acid either).

Third,after fixiing with RAPID fixer (ammonium thiosulfate only) give final water rinses, just three since rapid fixer clears very fast.
All water is from 5 liter pitcher, in which the film canister is immersed between agitations. Temp does not vary by more than fraction of degree over development times.
Denton
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I do not use stop baths for film either, I do for paper--

The most recent Rapid Fixes I have found did not have hardener , and I find hardener a good thing in film development, -- fixing scratches in emulsions is not a job I look to sign up for.

Regards, John
 
Denton said:
Prewet to bring film to developer temperature for more consistent temperatures and removes anti-halation layer.
Click to expand...
I just keep the film in the same room as the developer. Given development times and volume of solution I would be shocked if a pre wash had any effect on processing. I have never seen any scientific support for a pre wash based on controlled, correctly designed testing.
 
I don't shoot much medium format film these days, but when I do a roll, I'm always a bit shocked by the dark green water that pours out of the tank when I pre-wash a roll of Tri-X.
 
Prewet greatness is another urban myth. Right up there with stand developing.

Two things are important in first 30 sec after immersion. Developer must spread across the film dry edge to opposite as fast as possible. Never back track by tipping tank.

All pros I knew back then accomplished this by dropping the loaded reel into a tank prefiled with developer. In the dark naturally. Forget the nice funnel at the top for developer entrance. OK for exit and fix.
Commence agitation immediately. Use lift rod for more than two reels.

With plastic tanks, just pour in as fast as it will go. Tank design does it all for you.

The longer the film is wet, the bigger the grain.
 
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