Q for the experts: effect of temperature on final wash?

[tetrisattack]

So finally at school they trust me to run my own film through the coveted, jealously guarded Wing-Lynch Model 5 Rotary Processor. Now, after studying the technical details of C-41 and E-6 and even mixing the chemistry, I understand the kind of rigorous discipline required to keep finicky chemical processes in "control."

The scientific precision of the color processes has been spilling over into my b&w work, causing me to re-think many of my old habits. I'm much more precise about measuring chemistry now, I've switched to a two-bath fix routine, and I've begun to use tempered water baths to regulate my b&w temps over long development times. One thing occurred to me the other day as I was putting my film into the washing column: does temperature affect the efficiency of the final rinse?

Intuitively, it seems like an elevated wash temperature, say to 80 degrees from a processing temperature of 68f, might cause the emulsion to swell some and release more residual fixer faster. I'm not looking to cut down washing time per se; instead, my goal is to ensure that my film is washed as thoroughly as possible for archival purposes. I am using hypo clear as part of my normal routine, followed by a 15-minute wash at ~5 changes per minute.

The comments of any film-processing experts most welcome.

 

[bmattock]

I would not call myself an expert, but I do process my own B&W film and learn all I can about it. I understand that it is important to keep the rinse as close to the dev temp as you can - major changes in temperature can cause reticulation.

Best Regards,

Bill Mattocks

 

[ed1k]

I'm not an expert. Good advise you already heard: keep the temperature consistent thru all the bathes. Increase of washing temperature doesn't significanly help to wash, instead it gives the activity burst to the chemicals in emulsion. With high temp water rinse after developing you end up with overdeveloped negatives; with high temp final wash you unlikely to see "overfixed" negatives but it doesn't help washing process either, as well as you may end up with reticulation, get hardly disolved salts in emulsion or mechanically damage the film because warm emulsion is very soft. Be aware that "overfixing" is possible - fixer will disolve haloid silver salt and over some (long) time it will disolve metal silver as well eating shadow details (or highlights in positive process).
Two-bath fix routine is more useful for prints IMHO, but it surely doesn't hurt film. I never used hypoclear but I guess it doesn't hurt either 🙂

Eduard.

 

[FrankS]

Kodak and Ilford (and others) have done extensive testing on the processing of their films including the washing step. They have published procedures for this, and I would go with their recomendations: consistent temps. High temp washing may soften emulsions so much that damage is more likely if you physically remove water with a squeegy, spong, or fingers before hanging to dry..

 

[kully]

I can speak from experience on this. Washing in warm water is _bad_.

I've only been developing at home for a few months now and at the beggining I washed some HP5+ in warm water. Left the rolls to dry (for a couple of hours) then put them between clean A4 paper toi straighten, the emulsion(?) on the back stuck to the paper...

 

[tetrisattack]

Thanks for the replies --

I left reticulation out of my original post because I was only considering a gentle elevation in temperature, hopefully nothing risky. That being said, I do have considerable respect for ilford and kodak emulsions; having processed hundreds of feet of their film, I've never reticulated it, not even with my most grave faucet mishaps. 🙂 I'd be more gentle with efke or anything else rumored to be especially delicate...

Anyway, I'll keep it below 25. Scratched negatives are a bigger concern. Thanks again!

 

[John Bragg]

The effect of temperature changes during the wash can often be mistaken for coarse grain, when it is actually mild reticulation caused by the shock of the sudden change. There is also a school of thought that discourages the use of an acid stop bath because it too can shock the emulsion, and a water stop is recommended instead, though I have always used an acid stop, and never had a problem with it.
I always use the Ilford method of washing as it is easy to keep it to the same temperature as the dev, and saves time,water and effort with proven archival results and no need for hypo clearing agent .....
Regards, J.B.

 

[RML]

How about using cold water for the final rinse? My tap water is much cooler than the chemicals I use, and I never saw the use of using luke warm/warm/hot water for the final rinse. Cold water came only natural, but can it cause problems?

 

[Trius]

It's been said, but keep all temps the same. I process around 24C. I've posted this before, but there are some good tips on processing. (I disagree on his assessment of the stability of Rodinal, but that's another issue.)

Temperature control in the typical home darkroom can be a bitch; I'm still working on it.

Earl

 

[juggler]

Reading the above, does it mean I should develop, stop bath, fix and wash the film at the same 20C recommended for my TMax developer?

So far I have been doing 20C on the developer. But room temperatures for the stop bath and fixer. It's tough for me here to control the temperatures as the ambient temperature can be 25C to 28C even for nights.

I was recommended at a darkroom course to treat the development process as the most important. And choosing 20C to get a longer development time.

Come to think of it, even if I can control the stop bath and fixer temperature in an air-con room, the running water will be outside temperatures again - can be 30C or more for day time.

Another question: what is the Ilford Method of Washing?

 

[foto_mike]

I've tried to induce reticulation for effect. It's not as easy as you'd think. The developer is the only process that is greatly affected by small temperature differences. It's good practice to keep all of the process chemicals close to the developer temperature anyway.

I use a running tap water wash and I adjust the temperature to be close by the feel of my hand. I've never had a problem with insufficient wash or reticulation.

By the way, Ilford describes the Ilford way of washing developed film as follows:

"Alternatively, fill the spiral tank with water at the
same temperature, +/– 5ºC (9ºF), as the
processing solutions and invert it five times. Drain
the water away and refill. Invert the tank ten times.
Once more drain the water away and refill.
Finally, invert the tank twenty times and drain the
water away."

 

[hth]

After trying that Ilford washing method once, I will never try it again. Lots of small spots on the negs. I went back to my 30-45 minutes flowing water rinse and I do not even care to keep the same temperature, it is usually quite a bit lower. I have not seen any ill effects, but I guess I do not know what to look for. It looks fine to me and I am happy with the results.

/Håkan

 

[kully]

30-45 minutes!?!? I do 10 minutes of flow.

My film seems fine, but you've got me curious now. Does a long wash effect things like grain &c. or is it just to get rid of all the chemicals?

 

[hth]

I have seen no ill effects for the long wash. 10 minutes does not work for me, I tried it and the film was not clean. So nowadays I just let water flow at a small steady pace for some 30-45 minutes.

I do not test things to optimize, I just use it. If it does not work, then I try something else. I do not do any measurements or controlled testing. I just use whatever information I can find and was teached this long wash time from start. The few experiments I have done to reduce it have failed for me.

On the other hand, I really need to do a more controlled testing as soon as I can get my inkjet printer running again (2 out of 2 just ordered cartridges seems bad). I want to see what I can get out of it from good matte and rather expensive semi-gloss papers compared to my fiber prints. It is really needed to see in what direction to head.

Otherwise I avoid testing, I think if it makes me satisfied then it is good. I rather use my time for other things.

/Håkan

 

[pesphoto]

I usually wash for 30 minutes minumum. I do have to watch my water temp closely, as in the old house I live in the water temp can fluctuate at times. I'v seen the ugly reticulation others have spoke of. Actually, it's kind of cool to do once just to see what it looks like.

 

[derevaun]

I just fill a sink with water and adjust it to the developing temp I want, then I float capped bottles of whatever chemicals I'm gonna use (I mostly one-shot with Rodinal, so just water for that one). On cooler days the bath might drop a degree from start to finish, on warmer days it might warm up a little, but it's gradual.

I wash for less than five minutes. About a minute of first rinse, a minute of HCA, then a couple minute-long final rinses. It takes less than a minute for the residual fixer to equalize with a water bath, and I don't want to wash spent fixer down the sink with a running wash.