Rinsing film

[Erik Hartmann]

Just learned a (for me) new method for rinsing film.....
One fill with water .. 10 times aggregation... second fill and 20 times aggregation ... third fill and 15 times aggregation.....
Somebody called it the ilford way.....
Normally I rinse my film 1/2 hour... it takes a lot of water and the 'Ilford method' much less water. But do any of you know anything about The Ilford way (or is it called something else?)

erik

 

[clogz]

The Ilford Method is what I use. Some thorough research can be found here: http://www.largeformatphotography.info/unicolor/com_rolf.html

Hans

 

[Sparky]

The only problem with this method is that it assumes the thiosulfate has an equal attraction for the water as it does for the film emulsion - which I think is maybe fallacious. I really LOVE the idea- though think it should be amended with the addition of a hypo clear rinse - thus the problem will be transferred to the remove of the hypo clearing solution.

 

[clogz]

It would be very nice if the Ilford/Harman people could comment on this.

Hans

 

[jgcull]

My husband would like that and it may buy me some more darkroom time. We're in drought conditions and he keeps reminding me that there are water restrictions in neighboring counties. I'll give it a try!

 

[Dave Miller]

It has been discussed on this forum several times before, so a search may reveal the threads. The "Ilford Method" has been successfully used for many years, so there is no need to modify it or doubt it's veracity.

 

[ricksplace]

I use the "Ilford method". I have for years with no ill effects. Saves water and time too.

 

[Mick Fagan]

I have been using this Ilford method for years and years, works beautifully. We too have extremely low water supplies in many parts of this country and in some areas there is just no water.

For quite some time I was using running water using the Jobo hose with the air inlet which induced aeration and agitated the water. This supposedly reduced the running water from about 30 minutes to 5 minutes. I had nothing to lose at the time, water was in very short supply as it hadn't rained in over 1 year in that section of the country. This did work, but I was still worried about archival washing of film.

At this stage I read the Ilford method in a magazine and decide to give it a go. What I found interesting was that the amount of time taken to do the required inversions and fill ups was almost identical to the 5 minute wash with the Jobo hose.

I have used this Ilford method ever since, except when rotary processing, where I use a modified version of the Ilford method on the processor taking about 5 1/2 minutes.

Mick.

 

[Bob F.]

I think it is probably safe to assume that Ilford will have tested this method before releasing it to the world and that they tested it with lab equipment, and experienced chemists who know how to use it, far in excess of that available to any of us who are not (a) chemists and (b) work in a well equipped development lab. It is their reputation that is on the line after all. The only thing I would like to see is information that it has been tested lately by Ilford on modern films.

Depending on how I feel at the time I may use the Ilford method or use running water via a hose into the tank. Having said that, like I suspect many people who use the method, I still give one extra 20 inversion cycle "just for luck" and leave the film to soak in the Photoflo for a couple of minutes ...

Cheers, Bob.

 

[Photo Engineer]

L. F. A. Mason, in his book "Photographic Chemistry" does not use this method AFAIK. I have posted this before. He was a member of the Ilford research staff.

PE

 

[Erik Hartmann]

PE
Would you be so kind to give me (us) a hit whereabout I can reed some prove that I (we) shall not use the Ilford Method......

thanks
Erik

 

[Tom Hoskinson]

Here is a relevant APUG fixing-washing thread:

(there was a url link here which no longer exists)

 

[Photo Engineer]

L. F. A. Mason, "Photographic Processing Chemistry", Focal Press. Read the chapter on washing in which he shows the differential equation related to outward diffusion of hypo from film.

PE

 

[Sparky]

it seems clearly VERY sound to me - I don't see how you can go wrong - as long as you agitate (that's critical). Any level of knowledge in chemistry, physics and affiliated sciences really aren't going to be able to take the place of proper testing for residual hypo levels on the emulsion.

 

[Photo Engineer]

I'm really getting tired of this argument.

Diffusion is a continuous process and Mason shows that in his book. Others have too. If you don't wash in a continuously changing water supply, then hypo and other things build up and slow down the washing process.

Even with agitation there is a finite amount of exchange expressed as dc/dt or the change in concentration vs time within the film as a function of volume of water.

I have the book sitting right here next to me and I did when I answered the protestation in the last thread on this. Haist and others also disagree with washes that are not continuous.

Why take a chance?

Of course, you can do whatever you want to. After all, it might take 20 - 50 years to see if you have any problems so why worry.

PE

 

[pentaxuser]

Just thought I'd check the Ilford method. It actually says 5, 10 and 20. When you compare it to the continuous flow method of a tube inserted to the bottom of a tank and the wash times in the older books on processing then it does seem to be very little water by comparison and of course the Ilford method isn't continously emptying the contents as the constant flow method is. However a change to process and much less water isn't necessarily per se a less efficient process.

PE. I confess to problems with technical explanations and I have read the APUG link provided but didn't find myself much the wiser or at least not as wise as I'd like to be.

I haven't got a copy of the LFA Mason book and I fear I am unlikely to be able to get one and I haven't seen the Kodak method so can I ask you:
1. What is the Kodak method
2. Does L.F.A. Mason say what the problem with the Ilford method is?
3. If so what does he say, in layman's terms, if possible
4. What modifications, if any, to the Ilford method are possible which help overcome its problems

I appreciate the answers to 2&3 may answer Q4 and if so ignore Q4.

The Ilford method seems to involve 35 vigorous agitations which seems to be quite a lot but only 3 dumps so I am assuming that the problem involves the number of dumps as I would have assumed that the nature of 35 inversions presents quite a force to remove fixer from the film but not getting rid of the fix-contaminated water continuously but swirling it around the film may be key to the problem identified by Mason or it may be that even 35 inversions are not enough to separate the fixer from the film.

However I am speculating now and I would do better to wait for your response

Thanks

pentaxuser

 

[GraemeMitchell]

I've read the old posts and heard both arguments, and I personally use the Ilford method and then I let the film sit in a tank of running water for an extra 3-5 minutes while I prep other things, clean up, etc.

This is using Ilford Rapid Fixer. So no hardener. (Could this be part of the disagreement, some people using hardening fixers and some not?)

I do it to conserve water and save time.

 

[Photo Engineer]

The Kodak method uses continuous running water until the film passes 2 tests, namely the residual silver and residual hypo tests. Solutions for these can be purchased at most photo supply houses.

Mason effectively ignores the method that Ilford has posted on their web site, but he does say that one wash with a volume of X is 840 times more effective than 3 washes each one with 1/3 the volume of X, and therefore washing in continuously running water by the same analogy is infinitely more effective.

You see, the change in concentration of hypo in film depends on the concentration in the wash water and the time the film is in the water. If you don't maintain the concentration of hypo in the wash water at as close to zero as possible, then you cannot bring it to zero in the film.

Therefore, the only way to bring it to zero in the wash is by running the water all the time.

Mathematically this is: dx/dt = K[(a - x) - w] where

dx is the rate of change of hypo in the film
dt is the rate of change of time
K = a constant (depending on film, temperature, hardness etc)
a = initial amount of hypo in film
x = loss of hypo after unit time
w = amount of hypo in the wash water

The lower the value of w, the faster and better the wash is.

So, with a continuous wash, w = 0 (ideally) and is the fastest and best wash.

The method that he describes is a continuous wash of several tanks where fresh water enters the final wash, and then is circulated to the next from last and then second from last and etc until it overflows the first wash tank. During this period the film or paper is moved from the first (most contaminated) wash to the last through continuously running water.

This is the method that Kodak and Pako used in their processors.

The best method is to use running water for the time necessary to remove all residual chemistry to pass the test and it varies from film to film, paper to paper and from process chemistry type to type. I cannot give you an exact figure. You must test for the time yourself.

Dumps and inversions are NOT going to save you as the wash proceeds thusly. Lets say 50% of the hypo is removed in 10 mins. Then 50% remains. Then in the next dump, 50% of 50% is removed. In the next dump, 50% of 25% is removed. In continuously running water, the amount changes more rapidly and can approach zero more closely, as there is never any "w" left in the wash water.

PE

 

[fotch]

PE makes perfect sense to me. Even in bathing ones self, if you sit in a bathtub full of less than clean water vs. the shower with always clean water.

Hey, maybe take the film or paper with you in the shower

 

[Sparky]

It seems meaningless to even discuss this further academically - the only way you're going to prove whether the 'ilford method' works enough to give you a neg that contains a below-critical level of residual fixer is to do a rigorous test based on established standard target levels.

 

[Neal]

Hello All,

Just to add to the confusion, the wash method in my "Kodak Black & White Darkroom DATAGUIDE" (the capitals are on the book cover, I'm not shouting ;>) ) advises that after using hypo clearing agent the wash is for 5 minutes with a constant flow that allows for a complete change of water in 5 minutes (I read this as two tanks of water). It also mentions, as a speedier option, emptying and filling the tank 10 times but does not make note of any wait time between each fill and dump cycle.

The wash time without the hypo clearing agent is 30 minutes, but only requires about 5 or 6 tank volumes of water (the suggested flow rate is 1 tank per 5 minutes).

It seems to me that none of the methods mentioned by either Ilford or Kodak uses an inordinate amount of water.

Neal Wydra

 

[Les McLean]

Whilst not doubting Ron's (Photo Engineer) undoubted knowledge and understanding of photographic chemistry and other technical matters I have to report that I have used the Ilford Method for in excess of 20 years without any problems whatsoever. I do 5-10-20-15-10 and 5 inversions with a change of water at 68f for each step.

 

[Photo Engineer]

Les;

I have to agree that the Ilford method would have to have some merit or they would not publish it at all. Also IIRC, this method was developed when all of the British Islands were having a bit of a water shortage.

I would have to say that this is the minimum wash condition acceptable.

I would also add that IIRC, England uses ozone to purify water, whereas the US uses chlorine. This puts a tiny amount of peroxide or oxygen into the English water supply and peroxide is used to eliminate hypo.

All of these differences add up to say " use what works ".

PE

 

[Les McLean]

I would have to say that this is the minimum wash condition acceptable.

I would also add that IIRC, England uses ozone to purify water, whereas the US uses chlorine. This puts a tiny amount of peroxide or oxygen into the English water supply and peroxide is used to eliminate hypo.

All of these differences add up to say " use what works ".

PE

Ron,
That English purification methods puts peroxide into the water which helps eliminate hypo is interesting and prompted me to write the following:-

When I first started photography an old journalist told me to put a "splash" of peroxide into the tank and agitate for a couple of minutes and the film would be washed, hence speeding up the whole operation. I did this for a few months and then noticed that my negatives were changing colour, I recall being told it was dichroic fog that could be cleared by immersing the negatives in a mixture of citric acid and thiourea. I tried this on a negative and watched with horror as the emulsion turned to a jelly, slid off the base and floated away down the kitchen sink. (No darkroom in those days)

Luckily I had made no worthwhile negatives up to that stage in my photographic life so nothing was lost but I did learn a valuable lesson not to believe everything I was told and to fully check out obscure hints and tips before I employed them.

 

[Akki14]

Uh... I don't know about you but I grew up with well water so I can tell if tap water has chlorine in it or not because, to me, it smells like a swimming pool. At least in North London, there's chlorine, not ozone because it'd smell different wouldn't it?