Washing Film - Best Environmentally Friendly Way to Do It?

[Lee L]

So long story short...what is the recommended way to wash fiber prints for archival permanance?

Now that's just downright cruel.


Lee

 

[jim appleyard]

Jim;

Dry does not go with analog photography! (well, except for Polaroid)

PE

Is this like, "There's no crying in baseball!"?

 

[Photo Engineer]

Is this like, "There's no crying in baseball!"?

Not at all!

PE

 

[Claire Senft]

Except for the ease of doing the process the idea that one uses cascading water or that one uses a number of changes and then tests for retained hypo and proper fixing has a lot to offer in the way of being certain that every wash & fixing has been appropriate.

Ease of doing things, is for me, not very important.

 

[dancqu]

So long story short...what is the recommended way
to wash fiber prints for archival permanance?

There is no THE way to archival results. For those who
process in the usual way, develop-stop-fix, the use of
two fixers is best.

The wash prerequisite for archival results is a fixer
very little loaded with silver. So, a first fixer is used
to an established maximum silver content then a second
'clean' fixer used to bring the paper's silver load down
to a very low level. Best chemical milage is achieved.
The second fix which is very little loaded with silver
may be moved to first fix.

I use a single very dilute fix as a one shot so achieve
'archival' results with one disposable fix. Works well
with single tray processing. Dan

 

[CBG]

What is it that we're washing out of film anyways? What's it more soluble in? Water or gelatin?

Washing does two things mainly:
1. Washing removes fixer - we want to remove fixer from the emulsion and if printing paper, from the paper base. Fixer is necessary to make a permanent image, but needs to be removed once it has done it's work.

2. Washing removes fixation by-products. Fix converts undeveloped silver halides in the emulsion into soluble compounds, and makes washing possible. Washing removes silver fixation by-products from film. Fresh full strength fix makes the most soluble set of silver byproducts possible and therefore the most washable..

Washing must also remove any remaining developer and stop bath in the film.

C

 

[Photo Engineer]

Let me give a bit more history on washing.

Originally, texts suggested washing film in 5 - 6 changes of running water for about 30 mins to 1 hour. Prints on FB paper were about the same. In one case, it was due to the thickness of the emulsion layer, and in the other it was due to the DW FB paper requiring longer wash. I have alluded to this in previous posts.

Later, Kodak and others developed siphon print washers that used running water and a tray or tank siphon to change the total water in the container on a regular cycle of about 5 - 6 times / hour with normally running water. These recommendations are found in many Kodak publications in the 40s, 50s and 60s.

About that time, due to the concern over the environment, it was thought by some that still water with the same number of changes would give adequate washing. I discussed this with Bill Troop and he feels that much of the driving force came from England which had a water shortage in the 70s. Be that as it may, this practice was promulgated and began to be accepted.

With time, this 5 - 6 change of still water was repudiated by many as being unworkable. Well, the data seems all positive for running water, but variable for still water with agitation and changes. The equations by Mason show why. Buildup of waste products described by CBG in post 56 above enter into the picture as does the quality of the water and the operators expertise such as how well they drain prints and what kind of fixer do they use. It also depends on film and paper!

Therefore, the only "foolproof" method involves washing in running water. Any other method must be tested. In fact, I suggest tests be done with your condition no matter what you use. And, there are three ranges of wash, "normal", "archival" and "too much". Ctein has shown in his article on washing that if you overwash, you can cause problems with your prints just as much as underwashing. There must be just a tiny bit of residual materials left in the coating.

So, this matter is not simple and has no one answer. I say use what works for you, but test and don't overdo. Remember, hard water or film fix for prints can change your wash position totally, and FB prints on paper from one source may behave differently than FB prints from another paper source due to weight, baryta content and calendering.

PE

 

[dancqu]

Fresh full strength fix makes the most soluble set of silver
byproducts possible and therefore the most washable.. C

Fresh each roll or sheet of paper, that's the way I use fixer.
But "full strength" not by a long shot. My fixers are very dilute.
For each film or paper there is a certain maximum amount of
silver that can be Entirely complexed. I allow for that much
plus a little more. So much silver so much fixer.

I achieve good chemical milage that way. Of course it works
well with the single tray processing method. Or single tube
processing for that matter. Silver levels in the spent fix
are VERY low, 'archival' level. Shorter less water
demanding washes. Dan

 

[Photo Engineer]

Dan;

I say again!

This dilute fixer must maintain the silver complex solubility during the early stages of washing. I have actually seen dilute fixers work, only to fail when washing starts. Silver halide complexes re-precipitate out into the coating as the wash water begins further dilution and the complexes become insoluable again. They end up in the film or paper. Usually, film is most susceptable, but Baryta FB papers have been known to do this in the Fibre Base.

Sorry, but this is a fact. As many as 4 or more complexes form depending on fixer concentration and they all vary in soluability during the wash. One must be very careful.

You are making a broad statement that is not always true!

PE

 

[CBG]

... But "full strength" not by a long shot...

My reference to "full strength" was only to advocate the use of fix in good shape, that is, not worn out. I'll leave the battle on greater or lesser dilutions to others.

C

 

[dancqu]

Dan; I say again! This dilute fixer must maintain
the silver complex solubility during the early stages
of washing. PE

Although the fixers I use are very dilute they are not so
dilute as the fixers retained by a print or film which has
had a post-fix rinse-hca treatment. That is, at the earliest
stage of washing the retained fixer is less when the usual
post-fix procedures are employed.

A post fix in wash precipitation of silver halide I'd think
more a worry with the usual processing procedure. Few
I believe move prints directly from fixer to wash. I'm one
of the few. That is due to the one-shot nature of a very
dilute fix; one or a few at same time processed. The
fixer once used goes down the drain. Any home
brew or off the shelf fixer will do.

I don't worry about post-fix silver halide precipitation.
I've tested with fixers so dilute as to not clear, film
and paper. With correct amounts I've not noticed
any problems. Zero stains using Kodak's and
Ilford's formula HT-2 and the ST-1 test. Dan

 

[Photo Engineer]

Some advanced comments on washing

Last night (Saturday the 9th here), I was chatting in our chatroom while editing the fact sheet for the Super Universal Fix (tentative name for version VIII of the Super Fix). While doing it, someone asked me how many changes of water per unit time I used with running water and I answered, "I don't have a flow meter so I don't have an exact figure" which is a cop out!

I have measured the flow rate of my water using graduates and 4 liter jugs, but this too is a copout. It does not explain the matter fully, so here I go.

First, relating to one persons comments lets imagine a print lying on a tilted flat surface. Now, pour a liter of water over the print from the top down. The exchange rate is virtually infinite (dV/dT change in volume per unit time), but the volume itself is very low. Also, the bottom of the print sees contaminated water but the top of the print sees only fresh water. The wash is differential across the surface in spite of having a viturally infinite flow or exchange!

Now, consider 3 reels of 120 film in a SS developing tank. As water flows in at the bottom (assuming a delivery system such as Jobo uses to put fresh water in from bottom to top), then the dV/dT is relatively huge per unit area of film but again there is a diminishing but real difference in the quality of the water from bottom to top.

Enough water must be used in total so that the top reel of film is fully washed.

If you use static changes of water, do you measure the wash time as a total value or do you start and stop the clock as you dump and refill. It can take 30 seconds to refill a tank. This changes the way you have to look at wash time compared to the last two paragraphs.

Lets assume you use standing water and agitate by lift and dunk. On average, the bottom roll of film sees more fresh water during refill and more overall water during lift and dunk than the top roll. You have a differential introduced again across your film. The judge of extent of washing is again the top roll.

Well, this just illustrates the fact that washing is hard to define. It is a function of flow rate, container shape and size, and agitation methods for film and for paper alike.

Therefore, I don't judge wash as a measure of flow rate, exchanges or any other factor but rather - is it done at the end of 1 minute, 2 minutes, 3 minutes etc with my particular wash method whatever it may be. So, with a 5x7 tray, my flow rate would be slower than for an 8x10 tray, but for 1 print in an 8x10 tray it would be different than for 10 prints as would my agitation. This, just like photography itself becomes a lab technique (or an art) gained with experience, but only mastered by testing. If you don't test, you will not know where you are or were, ever.

The one sure thing I can say is that as you use ever shorter wash times, the number of changes of water per unit time has to increase. For example, Kodak recommended 12 changes of water per hour for a 30 minute wash or 6 full changes of water. With a 5 minute wash at that rate, there is no time for even one change of water regardless of method used, and therefore the change rate has to go up. This cycle of increasing changes as time shortens eventually is self defeating. But, with a 5 minute wash, 3 changes would seem to be the minimum to me. With the static water method, this 5 minutes would have to exclude the refill time of the tank or tray after each dump.

If wash rate dropped below 1 minute by some miracle of chemistry, then the flow rate would have to be huge, and there would be little gain in water usage.

So, these are facts to consider. Use the most efficient method of water flow and the most efficient way of timing and agitation. Test your results and if the results satisfy you then adhere to them all of the time with no exception.

Enclosed is a scan of a Kodak Hypo Test chart. Even though it is B&W, I am sure that you can visualize the densities as being pale yellow to darker brown from left to right.

That is how I test my fixers, my film and my paper for quality of washing.

PE

 

[dancqu]

Water restrictions ... I want to reduce the amount of H2O
I use as much as possible.
How do you wash your prints and films to use the least
amount of water possible?

After the fixer is out of the tank 500ml of wash water is
poured in and the first of Ilford's three wash sequence is
under way. No quick 5 inversions; they are spaced out to
allow for a more efficient use of the wash water. Same
goes for the following 10 and 20 inversion 2nd and
3rd washes. Actually I don't rush the washes at
all. Some little clean up and putting away is
also attended to while the film is washing.

Total wash water, 1500ml. To that I add another 500ml
for a PhotoFlo soak.

I could reduce my wash water TOTAL to 500ml by use
of the COUNTER CURRENT technique. By that technique
only the last wash is fresh water. That last wash becomes
the second to last with the next film to be washed. The
second to last wash water becomes the third to last
and so on. The first wash water is discarded. Likely
I'd use four washes as all but the last wash have
seen some use.

Now if one is really, really serious about skimping
on water, combine the counter current technique with
ROTARY TANK washing. Rotary tanks use perhaps 1/2 the
water. Likely a 5th wash a good idea. So, one could use as
little as 1 cup or 250ml of water to wash one 120 roll. Dan

 

[dancqu]

Some Reservations

I've not tested the counter current or the rotary or the
combination of both as methods of washing. So, I do not
recommend any of the three. My previous post is more of
a suggestion for use but any would need testing. If a LEAST
amount of water for washing film is a goal then any of the
three should be considered. Dan

 

[John Shriver]

Do devices like the Wat-Air film washer save any time, or do they just make it more sure-fire? Certainly is gets very good velocity on the water.

 

[Photo Engineer]

John, I cannot say as I never tested them. I have tested counter current and rotary wash as well as tank, basket and a variety of others. I have, in most cases, derived quantitative data in terms of mg/unit area of retained silver complexes and etc..

Thats about all I can say.

PE

 

[wogster]

Well guys, I'll post it again. BTW, I have re-read Mason and Jacobsen along with the Kodak technical manual. And Dan, your common sense is not correct here. Common sense told mankind that the earth was flat too, and the sun revolved around the earth!

Here are the equations for washing:

Diffusion rate governed washing dX/dT = k(a - X) where a = thiosulfate in the emulsion, X = loss in concentration over T which is time. This is read as the change in concentration per unit time.

This is an exponetial when integrated as in:

k = 1/T * Ln( a / a - x) where Ln = Log base 2

So, if 80% washes out in 4 minutes, then 20% remains and 80% of that will take another 4 minutes. No matter what method is chosen, the residual silver complexes and hypo must have fallen to a level that gives the best image stability. Now, this equation only works at the instant of immersion when there is NO fixer or complexes in the wash water such as in freely running water with agitation.

As washing proceeds in still water or agitated non running fresh water, the equation becomes:

dX/dT = k[(a - x) - w] where w = the amount of salts built up in the wash water at any given time! The larger w becomes, the slower the wash becomes and in standing water (say any of the 5 or so changes you use) it becomes larger with time and is NEVER zero. In running water it can be made equal to zero.

In addition, with FB paper, this equation does not apply at all due to the cellular nature of FB paper and the washing is very sluggish and can take up to several hours. So, this works only with film and RC paper.

Mason goes on (as does Jacobsen) to describe the ideal wash being fresh water introduced into a final tank which overflows into the preceding tank and soforth for a series of tanks connected together. Jacobsen gives the diagram of this countercurrent wash which has been used for years by commercial photofinishers.

Kodak simply says "wash the film in running water for 30 minutes..... at a rate sufficient to achieve about 12 turnovers / hour...". For FB paper it is 1 hour.

Refernces: L. F. A. Mason of Ilford "Photographic Processing Chemistry"

C. I. Jacobsen of Pavelle "Developing"

Kodak B&W Darkroom Dataguide (2 suggestions - one for normal and one for archival use. I have quoted the archival above)

PE

Considering the study was done with in the 1970's when hardening hypo based fixers were common, and now we have the rapid (Ammonium Thiosulphate) non-hardening fixers, does the studies findings even apply to modern films, prints and chemistries?

 

[Photo Engineer]

Yes.

Neutral and alkaline fixes were known in the 60s AAMOF. I sudied them extensively back then in a variety of equipment. And, I studied them across hardener types and with paper, across support types from FB to RC.

PE

 

[apochromatic]

Just to go to the Oz's original question regarding environment - I let my wash water run into the garden. Nothing's died yet plant-wise, I have plenty frogs in the garden though...

 

[Photo Engineer]

Yes, except for the silver complexes, Ammonium Hypo and related compounds found in trace amounts in the wash are benign or good for plants. Ammonia is a plant fertilizer at near neutral pH and in low concentration such as is found in wash water.

Blix and Ferric EDTA bleaches are good for Rhododendra, Azaleas and Oaks in dilute form.

PE

 

[ZoneIII]

From experience and testing, I know that the fill & dump method can be helpful if used in conjunction with the traditional constant flow method but, if dumps are too frequent, it wastes more water. As has been pointed out, fixer rinses out by diffusion. If you dump water too soon, your are dumping water that could have taken a lot more fixer. That said, I do totally drain my print washer a couple times during the wash but I have well water and have no shortage.

Many years ago, before I had a print washer, I experimented with print washing. I found a method where I stacked trays in a waterfall configuration where prints were first placed in the bottom tray and then transferred upstream when more prints were added. What this accomplished was it reused water from the upstream tray which had cleaner prints in it. The top (last) tray was fresh water. This was a rather cumbersome setup but it worked extremely well and test proved it. In fact, this principle is (was) used in a least one commercially available print washer in which the water moved sequentially from one chamber to the next, reusing the water for prints that had more fixer on them. It's a good idea but, in practice, it could involve more print handling. For many years, I use regular print washers which are easier to use in that you load them once and that's it. There is no moving of prints around.

Two ways to greatly reduce fiber-based print washing times is to be sure to use hypo clearing agent and to give the print a good rinse before it goes into a washer. I spray them off with a hand-held sprayer before putting them in the washer.

As other's have pointed out, the Ilford method is another option. I have used it but I still prefer the traditional 2-fixer bath procedure.

For film, I use one of those fill & dump washers which wastes water but I don't have a shortage of water.

I agree with those here who say that the most efficient method of washing prints is done in a print washer with a low flow rate and a periodic dump and refill, especially near the beginning of the wash cycle. If I lived in an area where water supply was an issue and I didn't have a print washer, I would use the Ilford method and hypo clearing and then rinse the print thoroughly followed by a series of water baths where the prints were allowed to sit between dumps. Agitation is fine but there is no need for constant or violent agitation. Just make sure the prints are not sticking together. I would dump more frequently during the first soaks. Since I have a print washer, I would essentially do the same thing except that I would use the compartments of my washer instead of trays.

For film, I would do essentially the same thing. In fact, that is basically the old Kodak recommended method for washing film and prints when water is scarce.

 

[ozphoto]

Again, thanks to all. I do use a print washer, and will start to use the fill and dump method. Apochromatic, I too water the garden with the wash water, this just means it won't get as much as it used too.

 

[dancqu]

A Favorite Quote. One From Fred Picker.

Quote: "No running water No agitation! Archival washing
requires time, clean water, and print separation"

www.fineartphotosupply.com/printwasherpage.htm

Read all or some more about it. I'm with Fred. Dan

 

[Jason Mekeel]

Hypo clear reduces the amount of water needed to wash film and/or prints.

 

[Photo Engineer]

Jason;

Most people forget that you have to wash out the hypo clear and that takes time and water as well.

PE