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
rich815 said:
Ok, we now have in this thread two completely opposite statements:

"One problem, theoretical, is that after the pre-wash the water now present in the emulsion may slow the developer in reaching where it needs to work"

and

"I cut development by 20% to compensate for the dev being able to take quicker due to the emulsion being wet."

So, which is it?
Click to expand...
Neither. Pre-washing won't change your development time at all. The first "theoretical" idea is just not true; the second idea, the practice of cutting development time might work well to produce great results, but it has nothing at all to do with the pre-wash. The practitioner has simply discovered a processing time that works with his method of exposure, his water content, temperature, and agitation technique. The idea that the pre-wash will reduce the time needed for development is nonsense- unless he's using water that has developing characteristics all it's own.


One other point about pre-washing- as some have noted, it tends to really help when you get into very short development times- say, less than 7 minutes.
 
I don't because I primarily use Diafine. A presoak is a _really_ bad idea with a two bath compensating developer... :eek: and the instructions say not to do it, too :angel:

William
 
What I would really love to learn, when reading this kind of discussions, is the hydraulic and chemical detail of the development process.

Prewetting, for example, is said to enable the developer to reach the active emulsion faster. Why? Because the water already soaked into the emulsion layers and the developer moves through the water.

Sounds reasonable.

The same goes for concentration and agitation of the developer. Higher concentrate will bring more developer into the emulsion to react with the silver halides. And agitation will allow for quicker refresh of the developer that's in the emulsion.

And then on a smaller level, what's the role of grain? What is a grain actually? A clob of silver halides? Is it the grain itself that is activated by exposure? Is a grain something binary: activated yes/no - developed yes/no, or is it capable of storing gradations? And about sharpness: Some developers retain the structure of the grain (e.g. Rodinal), others seem to break it down or soften it.

And how does all this work in the time? Highlights are told to develop first, while shadows come up later. Why is that? How is the dilution of developer evolving during development. Why can you e.g. stand develop for hours at high dilutions without much risk of burnt highlights? Is it just because developer runs out? What if you refresh developer or if you increase the volume? Will it still stand-develop safely for hours on?

Can someone recommend a good book that covers this process??

Groeten,
Vic
 
I'm with the "No, because Ilford says don't" crowd, because I use mostly Ilford film. The datasheet for my other favourite, SPUR Orthopan UR, also says not to.

If some datasheet says I should do it, then I will.

Easy :)

colin
 
vicmortelmans said:
... Can someone recommend a good book that covers this process??
Click to expand...

For cook-book type recipes, Creative Darkroom Techniques, by Kodak (no individul author listed.) How to do all sorts of stuff, before, during and after regular processing.

For a discussion of standard processing, The Negative, by Ansel Adams. It's all about fine tuning the process to control the characteristic light vs density curves. And more.

For the chemistry of film, The Fundamentals of Photographic Theory, by T. H. James and G. C. Higgins. A chemistry background is recommended for this one. It's from the 60's, and so, may not be fully up to date, but fortunately, not much has changed with film for the last 40 years!
 
Chris, that's good information! I already read Adams, but he's not in detail on the chemistry. Your third reference seems more like what I'm looking for!
Groeten,
Vic
 
When I lived in Cheshire I got to know a guy at Ilford pretty well, and he recommended against pre-soaking films. His view was that, while it had been a good idea with vintage films in order to ensure even development, with modern films it was a complete waste of time. Since then, I haven't bothered with pre-soaks unless the manufacturer expressly recommends it (such as Adox/Ekfe CHS films, which are essentially '50s technology anyway).
 
Lots of good info on this thread- thanks especially to Chris for the resources to check, and Mr. Phillip for his thoughts from his friend at Ilford. I think I'll keep pre-wetting most films, in the interest of not fixing what isn't broken with my processing technique; but I might try a few rolls (especially of Ilford films) without pre-wetting, and see if I can see a difference. Thanks all.
 
drewbarb said:
Lots of good info on this thread- thanks especially to Chris for the resources to check, and Mr. Phillip for his thoughts from his friend at Ilford. I think I'll keep pre-wetting most films, in the interest of not fixing what isn't broken with my processing technique; but I might try a few rolls (especially of Ilford films) without pre-wetting, and see if I can see a difference. Thanks all.
Click to expand...

What "film/developer combos" do you use with your pre-soak?
 
Where's the "only when appropriate" option?

I do it for TJ-Max films. Otherwise, the fixing step becomes a pain.
 
jan normandale said:
What "film/developer combos" do you use with your pre-soak?
Click to expand...
The developers I keep around all the time for regular use are Rodinal, HC-110, Microphen, Xtol, Diafine, and ID-11, although sometimes I am asked to use others. I shoot Fuji Neopan and Across, Ilford HP5 and FP4, Delta 3200, Kodak Tri-X and HIE. Clients send me all sorts of other films, too, from the usual suspects of APX, Delta, and TMax films to the occasional weird Chinese and eastern European films one rarely sees in the Midwest U.S.

I pre-wet everything except film to go through Diafine, and sometimes other divided compensating developers.

Thanks to the person who posted the wiki silvergrain page. I may try to do some testing without pre-wetting to see if I may get better (or at least different) results. One other point- I have never heard of pre-wetting being a strategy to eliminate air bubbles. When I process in closed tanks I always tap them periodically to dislodge airbubbles- even during the pre-wet stage.
 
drewbarb said:
The way it was explained to me, pre-washing helps in a variety of ways, including stabilizing the the film at the development temperature, and swelling the emulsion, preparing it for the developer. The idea is that this results in more even and consistent developing, and slightly finer grain.
Click to expand...

This is what I was told as well when I learned how to develope B&W films. I always do it for at least a minute before the developer.
 
Thank you for encouraging me to re-think my processing habits, Drew. I pre-soak 120 and 4x5 (5x4), but I'm not quite sure anymore about why I do this. For large format, the fact that my combi-plan tank takes some time to fill may have something to do with it. For 120, I vaguely remember a film that coloured even the stopbath with it's anti-halation dyes (or was the stop off?). I'll be following this thread with interest.

Dirk

P.S. I also presoak C41 to get the stuff at the right temp.
P.P.S. When I presoak, I do it for 1 minute, at dev temp.
P.P.S. I could not miss this opportunity to write 'P.P.S'.
 
You must log in or register to reply here.
Back
Top Bottom