Pre-wash of film - good or bad???

[joho]

I was thinking about this, when I read this on the last page[8] FOMA 200 film Thread.

So, I posted this new thread here ??.


as stated by Interneg.....[Chlororesorcinol as an anti-dichroic stain agent (which are now mostly incorporated in emulsions)....... Sooooo, if by washing out the dyes all together in pre wash of the film when developing the film do we recreate a condition for chemical FOG !??

[pchong]

I have been doing prewash. No issues so far.

[JLNims]

I'm not using FOMA, but I alway prewash and have never had a problem. I also prewash my color negative sheets before C41 and no problems there either. Maybe just with FOMA and possible other brands from that area in Europe? No offense Europe!!

[Drew Wiley]

I ALWAYS presoak. All films, all developers. No exceptions. No issues unless I don't do it!

[Andrew O'Neill]

Films that have a messy dyes, get a prewash. Those that don't, don't. I never prewash Ilford films.

[darr]

I always prewash. If you don't, all the dyes get mixed in with the developer plus what other crap might be on the film from handling it, etc. In 30+ years of developing film, always prewashed with no problems.

[Vaidotas]

It’s understandable beneficion of presoak keeping in mind antihalation dyes.
But there must be more technical explanation how developer works in two different aproaches.
I never presoak for short developing times and doing presoaking for dilluted developers with good results, but I have no arguments to prove this routine.

[Lachlan 717]

There is more to this than removing antihalation layer(s) - it is also to reduce “developer shock”.

This is especially true for larger formats where the addition of developer to the emulsion potentially causing uneven initial development.

The wet film can help to reduce this effect.

I use this for all my formats (now only 8x10 and especially 7x17) as there is increased time for the developer to reach the long end of the sheet.

[Tin Can]

i trust only Andrew as he has excellent show and tell











Films that have a messy dyes, get a prewash. Those that don't, don't. I never prewash Ilford films.

[ic-racer]

Not every choice has a "good" and "bad." For example putting the left sock on first, "good" or "bad?"

[Kevin Crisp]

Traditionally, the justification for a pre-wash was promoting more even development. I never understood how that could be. If I submerge a sheet of film in a tray, the developer contacts all parts of the emulsion plus or minus a fraction of a second difference. That tiny, tiny relative difference in the start time of development is never going to be detectable on the negative. And even if the film is already "wet," then it would still not be completely instantaneous. I've never done it with Kodak or Ilford films and had no issues. The two to three seconds it takes to fill a roll film tank doesn't make the deeper parts of the emulsion noticeably more dense, and that difference is far more than wetting a sheet of film.

Now if the FOMA green dyes are an issue that might be different. And I don't know what 'developer shock' is unless it relates to price.

[Salmo22]

I presoak Kodak films, and, like Andrew, I never presoaked Ilford films. This methodology has worked well for me.

[Michael R]

Largely agree.

I’m limiting my comments to B&W negatives.

Pre-soaking sheet film is important for tray shuffling if the sheets are added to the solution in relatively quick succession, so that they don’t stick together.

For all other processing techniques in tanks, drums etc. the traditional wisdom is that pre-soaking helps promote more even development where the film is not uniformly wetted (for example pouring solutions into tanks during which there can be splashing of developer onto parts of the film). However this seems to be based on the assumption wet film slows down development - ie that it takes time for the developer to increase in concentration within the water-soaked emulsion, whereas I have found the opposite to be the case - ie development starts faster when the film is pre-soaked, likely due to swell among other things.

Unfortunately it’s yet another one of those potentially contentious topics. Quite a few potential variables including the film, developer, processing, not to mention evaluation of development uniformity (you can’t rely on what users say works or doesn’t work). Lack of evidence, poorly written/ambiguous instructions unlikely to have been based on thorough testing, etc. Some people swear by it. Others don’t. Altitude, phase of the moon, planetary alignment…


Traditionally, the justification for a pre-wash was promoting more even development. I never understood how that could be. If I submerge a sheet of film in a tray, the developer contacts all parts of the emulsion plus or minus a fraction of a second difference. That tiny, tiny relative difference in the start time of development is never going to be detectable on the negative. And even if the film is already "wet," then it would still not be completely instantaneous. I've never done it with Kodak or Ilford films and had no issues. The two to three seconds it takes to fill a roll film tank doesn't make the deeper parts of the emulsion noticeably more dense, and that difference is far more than wetting a sheet of film.

Now if the FOMA green dyes are an issue that might be different. And I don't know what 'developer shock' is unless it relates to price.

[Gudmundur Ingolfsson]

Developing 120 film on reels especially on steel reels was disastrous till I took up pre-washing . I pre wet all films also Ilford and see no harm done to Ilford film.

[Tom Monego]

In my early years of large format photography, I never presoaked film and I would occasionally get air bells, what ever you call clear spots on the film. I started prewashing at the suggestion from a prof at college. Since then I have never had clear spots on my film. Early on I mostly used Super XX and TriX Pro. I then switched to TMax 400. I started using large format again this winter, with the cost of TMax films I started to use Ilford HP5+. This film has a lot of dyes that get washed out with the presoak. I definitely think presoaking is the way to go, Kodak or Ilford. I tried Foma100 with 120, but that is another thread.

[jnantz]

some people confuse religion with various aspects of photography. try both and do what you like and don't listen to the static telling you that you are doing it all wrong, there's always people who will say that ..

[Vaughn]

Toss in more variables such as the use of Jobo Expert Drums and their (Jobo's) recommendations, and it is pretty much about being consistent with what works best in one's space and workflow. Hi ho Silver!

[LabRat]

Pre-soak will start the removal process of the AH dye backing layer where it gets better removed during the rest of the process... And it can equalize the thickness of emulsion that dried, got hot/cold, old, swollen etc during shooting/shipping/storage that allows more even development over an entire sheet of roll of film... It worked with many makes/types of film...

I allow 5 minutes pre-soak with a drop per liter of Photo-Flo 200 (diluted 1:2) before all B/W processing and get perfectly even development (without airbells) every time...

An example was when I was supervising intermediate/advanced foto students, where one lady had returned from a whirlwind 12 city US + Euro trip carrying the same batch of 25 rolls of mixed brand/type of 35mm B/W films... She did everything correctly processing the first 4 reel processing run, but the films came out blotchy/uneven density along film, and dried with kinks along with the blotchy areas... I asked if she was air traveling, and she thought it might have been all the X-rays, but I didn't see fogging, just uneven development... Told her to pre-soak film for a few minutes before developer, and all the rest of film came out evenly developed and dried straight!!!

Very dry film seems to harden and not absorb developer like less dry areas, so edge areas could have dried more and give a different density during development... Or bulges can have different overall densities..


I think it's a must for film, especially after air travel, where the film starts to dry unevenly due to the bone dry humidity on airplanes...

Steve K

[rawitz]

Prewash in BW development never is wrong, but the question to expand, keep or even shorten developing time is not clearly answered. Maybe it depends on the film.
But prewash with Colorfilm is another issue. My C-41 process with sheetfilm 8x10 in Jobodrums sometimes resulted in uneven areas, as I found caused by uneven wetting at the start of the color developer (by rotating technic and reduced chemistry).
A 5 min water-prewash solved the problem, but there was a clear color-shift. Modern colorfilms have 3x3 color-layers stacked and the chemistry has to penetrate in an exact order, given by temperature and handling of the process. This is not any more given by prewash.

regards
Rainer

[Mark J]

Amazing stuff. I've never used a pre-wash in 35 years of developing rollfilm ( mostly ) and 35mm, most of this on stainless steel reels. The only film that ever gave me problems was Technical Pan on Paterson plastic reels. Other than this, ZERO problems. This includes air flights eg. coming back from Utah in 1999 with 28 rolls of 120.
Ilford specifically warn against it on all current datasheets : "A pre-rinse is not recommended, as it can lead to uneven processing".
The only other mention I can see in any datasheets, is Kodak saying that it can help in tray-processing of sheet film. I wouldn't argue with this.

[Salmo22]

That is why I do not presoak Ilford film and I've never had an issue after hundreds of rolls of 120 and countless sheets of 4x5. That being said, whatever works best for any photographers workflow. Some of my darkroom fun has been experimenting and determining what I like best. Even when a fellow photographer, whom I respect greatly, does the polar opposite. Variety is the spice of life...


Ilford specifically warn against it on all current datasheets : "A pre-rinse is not recommended, as it can lead to uneven processing".
The only other mention I can see in any datasheets, is Kodak saying that it can help in tray-processing of sheet film. I wouldn't argue with this.

[Duolab123]

I got started using water to warm up tanks before color processing. Seeing all the dyes was a "reward". Good doggy, here's your treat! :o

[Duolab123]

Pavlov's darkroom worker! :cool:

[Doremus Scudder]

Pre-soak if you have a good reason to. Don't if you don't. It's really that simple.

Doremus

[Duolab123]

Pre-soak if you have a good reason to. Don't if you don't. It's really that simple.

Doremus

:o Absolutely

[Roger Cole]

I started doing it routinely when I got a Jobo (including Ilford films) with no problems.

I did get uneven development on some 4x5 with the 2509n reels - I have a CPE2 - and yes I used the “bat wings” but pre wash or not didn’t seem to matter.

Now that I’m getting back into photography after several years I’m just considering splurging for a larger Jobo and Expert drums.

[Maris Rusis]

I reckon film pre-wash is essential where a relatively small volume of developer is used in continuous replenishment mode.

My Xtol-rep stock bottle has a volume of 2 litres and I replenish at the rate of 90ml (not Kodak's 70ml suggestion) per film. If I did not do a pre-wash the first 100 films through that 2 litre bottle of developer would have left about 90 films worth of dye still in the bottle after regular replenishment. And there are many dyes; anti-halation dye, spectral sensitisation dye, acutance dye, and speed trimming dye.
I don't think any developer can reliably cope with such a huge accumulating dye load and I'm not going to risk a row of films just to find out.

[Drew Wiley]

Uneveness in Jobo drums is often due to another cause, since their drums fill and drain slowly. I can fill or drain one of my 30X40 inch print capacity drums faster than a single-roll 120 film capacity Jobo drum.

[willwilson]

No pre-wet here, several thousand sheets of 4x5 and 8x10 Delta 100 processed. HP5 in lower volume, also fine. Most on unicolor drum with roller base, then jobo expert drums on a CPA.

I have been playing with Tmax 400 and ironically, I have been thinking about pre-wetting it but haven't yet and all fine so far. Very low volume though.

Test your thing then do your thing. Consistency is key for sure.

-=Will

[PunkFunkDunk]

I never pre-washed film in 20 years of processing. Never noticed any issues. However, as I recently started using Fomapan 100 in 4x5 sheets I now pre-wash that emulsion only since Foma’s dyes are so strong that of you don’t pre-wash the dye ends up contaminating the stop bath, fixer and hypo for re-use. I realise the dye likely has no effect on those baths but I err on the side of caution. Have not noticed any issue with pre-washing Fomapan 100 so will keep doing it.


Sent from my iPhone using Tapatalk Pro

[Roger Cole]

Uneveness in Jobo drums is often due to another cause, since their drums fill and drain slowly. I can fill or drain one of my 30X40 inch print capacity drums faster than a single-roll 120 film capacity Jobo drum.

If that was in reply to my comments, I do have a Lift, so it at least doesn't SEEM that slow.

In any case I'm concentrating on medium format for a bit until I can replace my elderly basically falling apart old Technika III. When I get a new (or new to me) 4x5 camera I may upgrade to a larger Jobo and the Expert drums at the same time. I've had no issues at all with my CPE2 and 120 or 35mm.

[Drew Wiley]

The slowness of filling and draining Jobo drums is due to the tiny opening in their funnel-like lids. I don't use any kind of lift, even on 30X40 inch drums. That makes no difference. I routinely use a Jobo hand-inversion drum for developing 120 black and white film, but have doubts about the consistency of the bigger print ones if short developing times are used.

[Vaughn]

Fortunately speed of filling has not been an issue yet for me (drums 3005 and 3006 on Unicolor motor base, 4x5 to 8x10). I give the film a good pre-soak, then it might take me up to 20 seconds to pour a liter of developer into the rotating drum. There is a limit to how fast one can pour into the drum without the liquid backing up.

On the 3005 drum, if I read it right, there is a 270ml minimum liquid recommended. So even if it takes me 20 seconds to pour in a liter into the rotating drum, I hit the minimum developer needed in 5 to 8 seconds -- after that, the speed-of-filling is no longer critical because all the film already has sufficient contact with developer that will not exhaust nor significantly weaken by the time I slowly pour in the other 730 ml.

Does that sound reasonable, Drew?

[Drew Wiley]

It's all relative, Vaughn. But it takes me only about 5 sec to fill or drain even one of my big 30X40 print drums during rotation because that is not reliant on a center hole, but entry through the entire light-tight rim diameter. Another thing that helps is to limit the percent of time of filling or draining relative to the overall time of development, for example, in RA4 processing, standardizing on 2 minutes instead one 1 minute. As per film itself, yeah, I'm convinced that a short pre-soak is essential to fast even spread and entry of the developer itself.