bill_troop1

The advice here is good. FX-1 is unlikely to require

a time less than 10 minutes or more than 12 minutes

on a conventional grain film. I would also try 15 minutes

with 10 seconds agitation on each 3rd minute. You

will be amazed by the results. Or horrified. Expect

grain, visible acutance effects, and huge impact.

Please also don't discount the fact that speed will

be 80-100% higher than D-76. My strong advice is not

to ignore this. Uprate the film at least half a stop.

You will not get quite the shadow definition that Ansel

Adams would ideally want, but you will get the maximum

practical sharpness you can out of small format film,

and shadows will be printable with a little work.

I have not used FX-1 in some time and would love to hear

where you are getting with times on the latest films.

Because of the carbonate, just as insurance, I recommend

not using a conventional acetic acid stop bath with this film.

If you want to stop development on the dot, use the

buffered acetic acid/sodium acetate stop bath I recommend

in FDC. Otherwise, a 60 second water rinse will be adequate.

If you are going to use a stop bath, the goal is to have

the pH be at least 4.5. Fresh acetic acid is quite a bit more

acid.

I want to emphasize that FX-1 will give a definite 'look' that

is not ideal for all photos. It's cruel, it's brutal, and it

even - gasp - could be said to incline to 'soot and chalk'

gradation. But nothing is sharper. Definitely one of my favourite

developers. As long as you don't expect everything to be

pretty-pretty with the most lush creamy greys, you'll be fine.

I am working on a very slightly less extreme variation for

Formulary, and hope to have testing done within in a month or

two more.

Lowell, while we're waiting for you to respond

with some times for Clayton CF Fixer, I have

another question. According to the Clayton store

section on 'digitaltruth.com', Clayton's

'Super Rapid Odorless Stop & Fix' is patented.

But no patent number is listed. A search of

the United States Patent Office site reveals

only one patent assigned to Clayton Chemical,

a method of rejuvenating rubber printing blankets,

number 5,326,590.

What is the number of the patent that covers

the 'Super Rapid Odorless Stop & Fix'?

>This thread is increasingly

off-topic. If you want to discuss anything beyond

the possibility that Clayton is providing inaccurate

information about its products, could you please start

another thread? I'm waiting to hear from people,

Clayton in particular, with some actual numbers

about their products. I suspect that's all that anyone

who clicked here is interested in learning about.

Ron & Ryuji, I am so annoyed you are starting a discussion on thiosulfate/thiocyanate, and wish you would start a separate thread, but since we are on the subject, I would like to say a few things.

My thinking has evolved considerably in this area since I last made some -- shall we call them rash? -- remarks on this subject during a thread with Ron which I hope we have all forgotten. A superficial reading of the literature easily provides the impression that thiocynate/thiourea solutions are not archivally suitable. For example, Haist, p. 597, "Today, the combination of thiocyanate and thiosulfate is often used for the rapid fixation of photographic materials, particularly for those applications where rapid access is more important than the long-time keeping characteristics of the image."

At first glance, this gives the impression that thiocyanate is something to avoid. But that is not the case. There is a simple reason for this. The historical fact is that the published formulas for thiocyanate/thiourea (TT) fixers were used for rapid stabilization processing, where there was no time to wash and no need for archival stability. Therefore, historically, there has been a tendency not to examine the potential of TT fixers in archival processing.

TT fixers have tended not to be used for materials where archival processing is desired because they are more expensive than thiosulfate solutions, and because extreme speed was not generally considered an important design consideration where archival processing was desired. There is also the fact to consider that even though TT fixers may shave off a minute of processing time here and there, washing times will still be as long as other processes unless there is very careful design of pH and other parameters.

In other words, TT solutions are luxury processes. There has also been the tendency to confine TT solutions to machine processing where every parameter can be controlled. One reason for this is that TT fixers must be very carefully designed to avoid reticulation or excessive softening of film and paper emulsions. Another is that thiourea-containing solutions must be handled more carefully than pure thiosulfate solutions.

A TT fixer for general use therefore requires considerably more testing and product development time than a conventional thiosulfate fixer.

All of that said, there is reason to suppose that TT fixers may confer archival stability significantly superior to pure thiosulfate fixers. Relatively recent research by Agfa and Ilford indicates that materials fixed in thiourea or thiocyanate may be substantially more archivally stable than materials processed in thiosulfate even under the best circumstances. It now even seems probable that a material fixed, for example, in a mercaptan fixer, may decisively benefit from a post-processing treatment involving thiocyanate or thiourea.

My conclusion is that TT processed materials, _when adequately washed_, may represent the cutting edge of what is currently achievable in archival fixing. I don't think Agfa Sistan represents the best way to use TT to confer additional archival stability for several reasons, including the application method. I think a carefully designed TT fixer, and carefully controlled washing process, may turn out to be superior.

As Conrad has pointed out, it is relatively easy to process films archivally. Some recent research postulates that the film base may be the limiting factor in the life of most negatives. But with prints it is a completely different matter. We need superior print stability, and TT fixers may turn out to be the best way to provide it.

Conrad, the fact that your RC prints are faring better than your fibre-based prints suggests to me that the fibre-based prints were not adequately washed. Washing with the acid fixers generally used at that time should have extended to several hours, and providing adequate agitation for several prints is not easy.

>Hello Ron: Have you seen a bottle of TF-4 ? It comes with an inch of "mud" in the bottom of the bottle. B & W formulas, without exception, should always be clean and clear.<

Lowell, it would be very easy to remove the mud from TF-4. But then you'd remove the active accelerant chemicals. Do you think it's possible that there's a reason TF-4 is five times faster than CP Fixer? Like, maybe, more, and better, chemicals?

In the meantime, we're waiting for your test results.

You have told us that CP clears film in 15 seconds. My tests on TMAX 400 show that in fact it clears 11 times slower: 165 seconds. Have you got any data to contradict this?

It only takes a few minutes to conduct a clearing time test, so what's the problem?

Does Clayton have a darkroom? Does Clayton have a test facility? Does Clayton actually test its products? Could you identify the chemist who designed your formulas? Where did you actually get these formulas?

Could Clayton state on the record just how long it takes your CP Fixer, fresh, at 68 degrees Fahrenheit, to clear TMAX 400 film?

>(Likewise, even TF-4 would require 1-3 minutes to clear when the solution gets partially exhausted.)

That's an important point, and why I emphasize testing clearing time throughout the use of a batch of fixer. Needless to say, when speaking of clearing time tests here, we are presumably referring to best possible results with fresh fixer.

I would like to clarify one fantastic piece of spin here.

Lowell writes,

"Through technology, we have been able to make this Sodium Thiosulfate formula work rapidly. Kodak also does it with 641 AERIAL FIXER/REPLENISHER"

Sounds like something pretty unique? "Through technology"?

Let's have a look at Kodak 641.

It's essentially a commercial version of F-9.

Lowell says "I don't know how Ammonium Chloride got into this discussion, but we do not use it."

Well, it belongs here.

Ammonium chloride was used as the agent for rapidity in Kodak's F-7 of 1942 (Russell, et al.). However, this agent attacks certain types of stainless steel (302 and 304, not 316). Hence, in 1947, Crabtree et al.'s F-9 formula, which uses ammonium sulfate at 6%, more or less the same amount as in Kodak 641.

So at first glance, this 'through technology we have been able to make' dates from 60 years ago. However, this technology had already been known long before. Precisely this indirect method was used in the Agfa Rapid Fixing Salt of 1906 (British Patent 25,869). And as a matter of fact, Haist writes, "The presence of ammonium ion in thiosulfate fixing baths as a means to secure rapid fixation was recognized as early as 1866 ..."

Lowell, would you care to comment on my suspicion that CF Fixer is essentially F-9/641 and that the accelerant is ammonium sulfate?

For the record, the speed increase of these sodium thiosulfate+ammonium accelerant fixing baths is not great, perhaps about 40%, although capacity increases of 50% were reported. You don't get the 400% over sodium hypo speed increases we expect today until you use ammonium thiosulfate or some considerably more complex technology.

F-9 was published with this caution: "With rapid fixing baths, do prolong the fixing time for fine-grained film or plate emulsions or for any paper prints; otherwise, the image may have a tendency to bleach, especially at temperatures higher than 68F. This caution is especially important in the case of warm tone papers."

Going back to an earlier question, neither sodium nor ammonium alkaline fixing baths do not bleach under any normal circumstances. There is no secret ingredient. It's a function of pH.

Lowell, thank you for the 449 words.

The part you left out is:

How long do you think it takes TMAX 400 film

to clear in your CF fixer?

It would only take two more words to answer that.

68 degrees F of course.

>I don't know if Lowell is the source of this data so it's probably unfair to blame him - but it's got to be in Clayton's best interests to conduct more accurate and thorough testing. Unless they have been conducting these tests while traveling at relativistic speeds, their claimed times are just plain wrong.

Al, you're absolutely right that Lowell isn't the source of

the data. But he is the source of the claim. May 10, 2005,

this forum,

"The interesting thing about our powder fix (CP FIXER) is that it will clear film in 15 seconds or less."

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00C8Xl&unified_p=1

I'd sure like to hear from Lowell with some test results.

>if TF-4 clears TMY, a notoriously difficult film to fix, in 30 sec., what is the recommended fix time for TMY in TF-4? If we use the old rule of 2X clearing time, that would suggest a 1min fix time. Is this correct?

Jay, the time I gave was for dry film. Clearing time for wet film

would be a few seconds longer. With Tmax films, you generally leave

it in the fixer a little longer to remove more of the dye. I recommend

twice the clearing time for ammonium thiosulfate fixers. For

sodium thiosulfate fixers, used with modern films, I recommend

3 times the clearing time. That means the recommended fixing time

for TMAX 400 in Clayton CF would be 9 minutes. And that's only when

the fixer is fresh. Fixing time increases as the fixer is used up.

I noticed in a recent thread called 'fixer of choice?' that Lowell

Huff claimed Clayton's CP fixer will clear film in 15 seconds or less.

I thought this was impossible, and decided to put it to the test.

I took some 2" strips of T-Max 400 (a little old, circa 1997) and

processed it in fresh CP Fixer, mixed according to directions, and in

my own TF-4 fixer, mixed according to directions.

TF-4 cleared the film in 30 seconds.

Clayton CP Fixer cleared the film in 2 minutes, 45 seconds, or 165

seconds.

In other words, Clayton CP, according to my test, is about 5 times

slower than TF-4, and about 10 times slower than it claims to be.

This is what I would expect for a relatively primitive powder formula.

Has anyone got any other results/comparisons tabulated?

A side note: TF-4 really does remove a considerable amount of the

magenta dye.

N.B. I processed with dry film. Results with wet film, or processed

film, should differ, but not substantially.

I intend to do some more extensive testing as time allows, with

different films and different pre-treatments.

But I don't see anything that could possibly support Lowell Huff's

extravagant claims about this product.

Lowell - have you actually tested this stuff? Would you care to

publish some results? It would especially be interesting to see the

results of your tests when compared to TF-4.

I would be interested in hearing from anyone who has actually tested

film (and also paper) clearing times with Clayton fixers.

Ron has a bee in his bonnet about edge effects, and for good reason. His is the only prominent voice out there noting that you don't always want edge effects from your developer. I wish we had discussed this more in FDC, and had managed to produce illustrations showing the quite different edge effects that you will get, for example, if you shoot the same subject on 35mm film, and on 4x5 film, but develop in the same acutance-enhancing developer and by contrast the same non-acutance developer. Geoffrey Crawley has well-described the situation that occurs in a dilute developer: each frame becomes its own little developing lab. The corollary is that processing uniformity goes out the window, and processing uniformity is very important to Ron. Personally, I'm willing to take the risks. I don't, myself, mind, all that much, if a frame has bromide marks around the sprocket holes, or if there is halation, or other gross edge effects that you will tend to see using extreme acutance techniques such as stand or near-stand development. But the perspective of one who keeps conventional technical excellence uppermost in mind is always welcome. It really is a complex situation that deserves more discussion.

All of that said, I don't think that a water-rinse, in and of itself, is capable of _drastically_ altering the degree of edge effects in development. Yes, a water rinse will enhance edge effects - often for the good, and occasionally for the bad. But to get a _very_ high degree of edge effects, you must develop in a very dilute developer, and must agitate substantially less than normal. Conversely, to avoid edge effects, you must use a developer that will not exhaust much, and must agitate normally. In either case, the major effect you get - low acutance or high acutance - will be set by the way you developed, not by whether you used a true stop bath or water rinse.

In other words, if you have developed for low acutance, and use a water stop, you will gain slightly more acutance than if you used a stop bath. If you have developed for high acutance, you will only get slightly less of an acutance effect if you use a stop bath instead of a water rinse.

My thanks to Ron for letting me know about this interesting thread. I did not realize that the instructions for TF-4 have a blanket advisory against using acid stop baths. I will have to look into that. There is a brief section in FDC on p. 106 which sets forth a useful technique for employing acid stop baths with alkaline fixers (or neutral fixers, or near-neutral fixers -- for example, slightly acid fixers where you do not want to raise the pH to neutral, as could happen if you used a typical acetic acid stop bath):

"It is possible to use acid stop baths with alkaline fixers when you need to stop development on the dot and in order to suppress edge effects--for instance in scientific photography and astronomy. Simply rinse the film in running water for 30 seconds _after_ the stop bath but before the fixer. This will keep acid from being carried over into the fixer. Alkaline stop baths are still experimental. See Appendix 1 for suggestions."

In other words, yes, you should not place an acid bearing material straight into TF-4 -- even though it is so well-buffered that pH would still probably not fall below neutral. Instead, you should wash briefly in water, after the stop bath and before the fixer. Under those circumstances, you will still be getting the rapid washing benefits of alkaline fixers. (Even so, you would need to add a _lot_ of acid to TF-4 before you reduced the pH to the point where rapid washing did not take place. TF-4 is very well-buffered--that is why there is a sediment in the stock solution.)

However, let's look at some other things.

1. The important point has been raised that using a stop bath saves on water. This is absolutely true. However, an all-acid washing sequence will _not_ save on water ultimately, because although water is saved at the _stop_ step, much more water is needed at the _washing_ step.

2. As Ron points out, the stopping of development has never required a pH change. (Lowell, since you aren't aware of this and yet do manufacture photo chemical products, let me tell you that there are suggestions for experimental alkaline and neutral stop baths in FDC. Why don't you have your company put some R&D into them? That would be a valuable service to photography.) Stop baths can be made at any pH. However, I doubt that any practical neutral or alkaline stop bath is as _rapid_ as the 10% buffered acetic acid/sodium acetate stop bath solution I recommend on p.104 of FDC. That's an expensive stop bath to use, compared to 2% acetic acid, but it works so much better, and avoids the possibility of pinholes and reticulation, that I can't understand why anybody who needs to use a stop bath wouldn't use it. However, of all the suggestions I have ever made, it seems to be one of the least popular.

3. Intuitively, it seems to me that if you are going to use a stop bath, it is much more elegant to use an acid fixer as well. However, you will still be using much more water because of the longer washing times you need, and that unnecessarily consumes both time and water, two resources, especially the former, we can never have enough of.

4. I realize I am flogging a dead horse, but let me reiterate my belief. If you are going to use a stop bath, there is no point in using one that doesn't stop development rapidly. 2% acetic acid does not stop development rapidly. 10% buffered acetic acid/sodium acetate does. The very elegant Kodak study which sets this forth is "Replenishment of the Film Stop Bath", PSA J., 17B: 13 (1951). That is one of many references I should have but did not include in FDC.

I would like to respond to the comment,

"Unfortunately, Anchell gives no references for this (or for much of anything else in

his book for that matter. Parts of The Darkroom Cookbook were lifted virtually

unchanged and unattributed from the British Journal of Photography)."

If you are talking about Steve Anchell's 'Darkroom Cookbook', you may well be right -

I haven't read it since I made some comments on the very first edition.

But if you are talking about the Film Developing Cookbook, which is an entirely

different book that I co-wrote with the redoubtable Steve, that is a different story.

Start with the bibliographical note on page xi, which defines BJ as British Journal of

Photography. Go back to the acknowledgements on p. viii which states that "Geoffrey

Crawley, for many decades the editor of the British Journal of Photography ... has ...

for almost two decades ... unreservedly given us the benefit of his expertise.

Now turn to p. 44 and the heading, "Geoffrey Crawley and the FX series of developers"

- and you will see one of the most highly attributed pieces of writing in the entire

scientific or popular literature.

Also consider that the entire manuscript has been read, several times over, by

Crawley, as has the first and subsequent printings.

My curiosity piqued, I have just spent several minutes riffling through Steve Anchell's

"The Darkroom Cookbook, 2nd Edition, 2000." I find no extensive or even minor

quotes of Crawley whatever, though a few of his formulas are represented. The only

book in the entire photographic literature that I know of which quotes extensivvely

from the BJ is mine. So I think it must be my book which is meant here. But I cannot

find any quotation from the BJ in my book which is not carefully attributed. Am I

missing something? I would be extremely grateful for clarification, as would Mr

Crawley.

Let me respond to Messrs Hicks and Keyes on a point that Mr Hicks seems to feel so

strongly about that he has posted about it in multiple threads, namely, what he thinks

is my error in asserting that, on page 107 of FDC, 1st edition, when water is in short

supply, five rinses, lasting five minutes each, are desirable. This is Kodak, Harrow

research, not Ilford research, as Mr Hicks writes. I know of not a single scientific paper

from Ilford on this issue, and Mr Hicks does not cite one. But there are four from

Kodak. Let me repeat my response when this question arose in another thread:

Bill Troop , feb 01, 2005; 03:12 a.m.

I would like to respond to Roger Hicks who writes,

"Do not automatically trust Anchell and Troop. There are a lot of unsupported

assertions that are not widely accepted by other authorities; many opinions

masquerading as statements of fact: and some flat errors, such as their strictures on

film washing on page 108 where they state that the film must be left to soak five

minutes between sets of inversions. I know the people at Ilford who did the original

research -- one of them is or was on the ISO standards committee -- and the five

minute assertion is pure fiction. It would not be quite so bad if A+T did not say that

the way without the wait 'is an error'."

Roger, for my five-minute statement, why don't you have a look at the following three

papers?

1. G.I.P. Levenson (Kodak, Harrow), "The washing powers of water", J. Phot. Sci., 15:

215 (1967).

2. A. Green and G.I.P. Levenson, "The washing of thiosulphate from gelatin layers", J.

Phot. Sci., 18:1 (1970).

3. G.I.P. Levenson, "The economics of photographic washing", Brit. Kinemat., 30:95

(1957).

There is also a fourth and very well-known paper by Levenson if memory serves me

(all of this research was done by Kodak, Harrow, not Ilford which simply incorrectly

appropriated it) from the mid-1970s for which I do not conveniently have the

reference.

Then you may want to glance at Haist, Modern Photographic Processing, vol. 1, p.

668:

"For efficient washing of photographic materials a complete change of water in the

vessel should be made every five minutes .... Five or six 5-min changes of water are

sufficient to insure permanence of images on film or glass supports."

If you have any other "unsupported assertions that are not widely accepted by other

authorities; many opinions masquerading as statements of fact: and some flat errors"

that you suspect I have fallen into, I would be delighted to address them here or

anywhere else. I am one of the world's most accessible people. Please feel free to

email or phone me anytime. Sincerely, Bill

P.S. The url for corrections in FDC is www.graphos.org. Every known error in every

printing of FDC is enumerated there, as is every change in each of the four printings

of the first edition. I have dozens of times begged the community to let me know of

any desired corrections to FDC. People of the calibre of Grant Haist, Howard (T.H.)

James, Geoffrey Crawley, Silvia Zawadzki and Dick Dickerson, to mention just a few,

read every word of the manuscript over many years and offered detailed comments. I

don't know why people like Keyes and Hicks cannot show a similar spirit.

P.P.S. Regarding the issue of capacity and the 1:1 dilution of D-76, readers should

consult Bob Schwalberg's articles on the subject. His tests were extensive, and were

eventually validated by some key scientists at Kodak - who, however, would not

permit their validation to be made public. Film and developer are still awfully cheap

relative to the cost of making a photograph good enough to warrant preservation.

What is the point in being stingy with developer and getting sub-optimal results?

I would like to respond to Kirk Keyes's comment:

I'm glad you have Henry's "Controls in Black and White Photograhy". I think that

should be in every serious B&W photographers book collection. And I was just going

through an old copy of the Kodak F-5 Publication - that one really does have a lot of

really good, solid, concise info in it. And of course another vote for the Ansel Adams'

series.

"I'm very disapponted in Anchell and Troop's "Film Developing Cookbook". Not a

single graph or chart in the book. The language used to describe many film/developer

combinations is often vague and imprecise. How can you talk about film developer

combinations without giving a graph of the development curve. It seems very well

researched, but it appears to me that the book is just a collection of info and

anecdotes collected from various places, with very little real testing done. Much info is

given without any rational behind it, unlike Henry's book."

Kirk, the reason we didn't include any development graph curves is that there weren't

any published curves we thought were useful. Personally, I believe the only recent

valid sensitometric work is that done in the late 90s by Dickerson and Zawadzki at

Kodak, and that is not available for publication. I have encouraged those scientists to

publish it, but they believe it is out of date and in any case not extensive enough to

be definitive. My response is that it is more extensive than anything else that anyone

has ever done. But their standards are such that they think it would be counter-

productive. With this viewpoint I am in some sympathy.

Regarding Dick Henry and the general difficulty of making any kind of valid

photographic measurement, let me quote from a letter he wrote to me on 7 Oct 1983.

I had just informed him of his (and most other writers') error in assuming that light

meters were calibrated for 18% reflectance.

"Dear Bill,

I talked with Ansel Adams and he was shocked to hear that meters were being

standardized against 10% reflectance density. He said he would be making inquiries

back East about this. No bookstore here has the 4th ed. of Dunn & Wakefield. I will

order it tomorrow but it may take 4-6 weeks to obtain it. I will also have to obtain a

standard to make sure that I am measuring what I think I am measuring. You will

eventually hear from me but it may take some time. We appreciate your bringing this

to our attention.

Sincerely,

Dick Henry

I would like to respond to Roger Hicks who writes,

"Do not automatically trust Anchell and Troop. There are a lot of unsupported

assertions that are not widely accepted by other authorities; many opinions

masquerading as statements of fact: and some flat errors, such as their strictures on

film washing on page 108 where they state that the film must be left to soak five

minutes between sets of inversions. I know the people at Ilford who did the original

research -- one of them is or was on the ISO standards committee -- and the five

minute assertion is pure fiction. It would not be quite so bad if A+T did not say that

the way without the wait 'is an error'."

Roger, for my five-minute statement, why don't you have a look at the following three

papers?

1. G.I.P. Levenson (Kodak, Harrow), "The washing powers of water", J. Phot. Sci., 15:

215 (1967).

2. A. Green and G.I.P. Levenson, "The washing of thiosulphate from gelatin layers", J.

Phot. Sci., 18:1 (1970).

3. G.I.P. Levenson, "The economics of photographic washing", Brit. Kinemat., 30:95

(1957).

There is also a fourth and very well-known paper by Levenson if memory serves me

(all of this research was done by Kodak, Harrow, not Ilford which simply incorrectly

appropriated it) from the mid-1970s for which I do not conveniently have the

reference.

Then you may want to glance at Haist, Modern Photographic Processing, vol. 1, p.

668:

"For efficient washing of photographic materials a complete change of water in the

vessel should be made every five minutes .... Five or six 5-min changes of water are

sufficient to insure permanence of images on film or glass supports."

If you have any other "unsupported assertions that are not widely accepted by other

authorities; many opinions masquerading as statements of fact: and some flat errors"

that you suspect I have fallen into, I would be delighted to address them here or

anywhere else. I am one of the world's most accessible people. Please feel free to

email or phone me anytime. Sincerely, Bill

>Just for the record, color and B&W are closer than you might imagine. I don't expect you to believe that, but some examples might help. Color and B&W products use the same hardener, at the same level, except for X-Ray. (we discussed that before)

I do believe it, since you put it that way, for Kodak films, and I am glad about it. Have you any idea if that level of hardening also applies to non-Kodak b/w films? I get the very general impression that Agfa and Ilford films are now hardened much better than in previous decades, but what about the Eastern European and other films of that ilk? I realize that such information if it is known might be considered quite confidential, but equally, it would not surprise me if nobody at Kodak actually had it.

A separate issue, given the quality of present day hardening of Kodak black and white films: what would you say would be the maximum, not just safe but desirable, processing temperature without additional hardening?

>Pyrogallol and pyrocatechin ... relief image can stress and crack an image badly under certain circumstances.

Can this exist at a point where it is not necessarily evident by visual examination of the negative but where an enlargement is not usable?

>The illustration of rupture of emulsion with pyrogallol developer (reticulation) is shown in fig 396C, Page 1040, Mees "The Theory of the Photographic Process" Revised edition.

That is fascinating. I can't look it up as I have just packed up

most of my books preparatory to an unexpected move. Are you referring to the 3rd edition of 1966? (I am guessing that; I think the 4th of 1977 no longer has Mees's name.) I wonder if Gordon Hutchings is aware of that. I think that's one thing he might have missed although he has studied closely nearly everything that has ever been published on tanning development.

>It can be decreased by slowing the drying, as this effect is caused by the rapid drying of the less swollen areas of the emulsion due to the tanning effect.

Can you suggest a way of accomplishing that in an ordinary darkroom? That is to say: is there a practical way in which we can dry film slower than by just hanging it up at room temperature?

I suspect that many of the recticulation or reticulation-like effects I have seen in tanning developers can be avoided by using distilled water; in other words, that too rapid drying is not the cause in many of these cases and instead is due to some unknown reaction between the chemistry and minerals in whatever tap water is causing the problem. But I still occasionally hear of an obstinate case and now wonder if it would not be good practice to advise some method of slower drying when using tanning developers. Needless to say, no manufacturer today could be expected to make a film with tanning development in mind. Perhaps your suggestion is the key to the few remaining obstinate cases where reticulation is still sometimes experienced with tanning developers?

Finally, here's a question you might know the answer to, or might be able to pose to W.E. Lee if he is still alive. In 1982, he stated publicly that he was working on a fixer that would promote improved stability of black and white materials, and that the formula for the fixer would in due time be published. As far as I can recollect, that formula was never subsequently published, for whatever reason. It would be interesting to know more about this. Did the work pan out in an unexpected direction? Did it have to be terminated before it could be completed? It's a tantalizing puzzle - unless of course, the formula was published and I simply missed it.

>It seems we do agree on some things. You see, we each can learn from each other.

There will inevitably be clashes between those who focus very widely, for range of knowledge and those who focus very narrowly, for depth of knowledge. Each type has value, but they are polar opposites.

>I am sure that they could not share with you due to its proprietary nature.

My experience is that if you know the right question, you'll get the right answer, but you do have to know the question and your interlocutor has to be in the right mood.

>I was disturbed by your complete dismissal of the knowledge that I have and the insights that I have gained, and the words you used to dismiss them.

Oh well, same here.

>The Mowrey, Stephen, Wolfarth patent # is 3,706,561. I don't have the # of the Stephen and Surash patent.

I wish you could dig up that number somehow. The US PTO website is set up such that you can't search for authors before 1976, and Surash is only listed as the inventor of 3 patents after 1976 - there must be many dozens before that point as his name is always coming up.

>It was due to my extensive process development experience, particuarly in color, that Grant Haist asked me to help him edit his book.

It IS mightily impressive - in color.

>I suggest that you consider it carefully before you dismiss my work and career so cavalierly.

Like I said, when you get two guys in the same room, one of whom knows everything about a few things, and the other of whom knows a few things about everything, sparks must fly. Naturally, the admiration of the generalist for the particularist is unbounded, because the generalist knows he can only get the information he needs from the particularist.

>I mentioned the Formulary sale of Glacial Acetic Acid merely to indicate that they sell it to amateur photographers.

Shocking! I wouldn't do it myself. But I have got to the point where I really don't like to be around chemicals and have adopted something of an extremist safety position. That said, I think we struck a reasonably good balance in FDC between both sides. I had a very hard time convincing my co-author to use neoprene gloves, but he likes them now, and as for publishing Richard Henry's idea that you should dissolve a packet of, for example, developer, by opening a corner, then submerging the corner in water and emptying the packet that way, he said it was impossible to do, until he tried it, and now he likes it. Now, I can't expect you to sympathize with that viewpoint, but I think it is the most responsible viewpoint to take as far as public utterance goes. Yet, on the other hand, in perfect fairness, I have heard more than one long-lived chemist say that he believed he was alive because the horrible chemical exposures he suffered from a lifetime of work must somehow have boosted his immune system. The idea being that a sub-lethal dose of the poison can strengthen you. Now that really is anecdotal persiflage, but I have heard it from several reasonably distinguished chemists. So there one is.

One final point, if you look at the arguments here, you'll see that a lot of it is due to three simple facts: (1) my focus is black and white; (2) your focus is color; and (3) black and white films have never been as well-hardened as color films so that experiences in extreme solutions can be quite different. (It is also likely that some of the films available today from non-major sources are still hardened with 1950s level technology.) Haist often bemoaned the fact that black and white films were not hardened adequately; he believed that hardeners in processing solutions should never be necessary. Now we all know that since the 1980s, black and white films _are_ much better hardened than they were. But I would be very surprised to find that they were hardened as well as color films. Do you have anything you can say about that with regard to hardening when comparing the latest generations of black and white films with their color counterparts?

Relating also to hardeners, could you say anything about the syndrome where users of pyrogallol and pyrocatechin have had more than their fair share of reticulation-like experiences, especially when not using distilled water? Haist has very generally and preliminarily theorized that this could be due to interaction with the hardeners used in the films. If I remember what he said correctly, it was something very general about the 'broad molecular structure' of those particular developing agents.

Ron, thank you for your informative post. I just want to clarify a few points:

>How do you rebut the concentration of Kodak Stop bath?

I don't rebut it, I point out what ideal practice is.

>The Formulary sells Glacial Acectic acid Bill, and you ignore that.

Ron, I have no connection with Formulary other than that they sell some products I formulated. I can't control what they sell. In fact, I don't even know what they sell, outside of my products.

>As for the stability of silver images, there is some evidence that the silver image is preserved by the formation of a deposit of sulfides on the surface of the silver. This is anecdotal and not hard evidence, and results from the observations that a little hypo must be left in the coating, hypo decomposes by being oxidized, liberating sulfur compounds, and oxidation is involved in destruction of silver images. Taken together along with finding silver sulfides in the processed films and papers give some anecdotal evidence that silver sulfide stabilizes the surface of a silver image.

Ron, you use the word 'anecdotal' twice in this paragraph. That evidence isn't anecdotal, it is published. Let me refer you to the SPSE International Symposium on the Stability and Preservation of Photographic Images which took place August 29-September 1, 1982, at the Public Archives of Canada. Klaus Hendriks was the General Chairman of the Committee. Session 5 was Stability of Photographic Silver Images.

Drago and Lee read two papers; there were also papers by Beveridge and Cole at Ilford, Minigawa and Torigoe at Fuji, Tullis at Polaroid, Kopperl and Larson at Kodak, and finally Owebach at Kodak. As far as I know, most or all of these papers were subsequently published in journals. The evidence presented was not anecdotal. It was as factual as the science of the day could make it.

I would further point out that Lee described the use of Kodak Rapid Selenium Toner as desirable. Let us not forget that KRST is not just a toner, but is also an alkaline ammonium thiosulfate fixer. Lee also noted that 'the use of Kodak hypo clearing agent to reduce washing time is less desirable than using the full wash period', which goes to Garry's point.

The gist of several of these papers is that some thiosulfate residual is desirable.

What will particularly interest you, Ron, and is very on target for the discussion of your fixer, is the following remark of Ilford's Berveridge and Coles:

"Analytical examination has shown that processing in a thiosulfate fixing bath provides a silver sulphide surface considerably improving the image stability. Compounds such as thiourea reinforce the sulphide layer and give further improvement to image stability, however, formation of sulphide from this source does not occur during processing but subsequently by decomposition of the adsorbed compound."

My points are two: thiourea, at least according to the Ilford scientists, appears to assist in stability in a manner that you may not have been aware of and I must certainly admit that I had completely forgotten this; and the evidence is not anecdotal. These papers were read at an SPSE conference and whether they were subsequently published or not, their findings are not anecdotal.

>As for washing, todays films and papers are considerably different than some of those investigated by Bill Lee.

Especially given that he was primarily working with spectroscopic plates. However, he believed that his results were extrapolable to most b/w photographic materials and most subsequent readers of his papers have accepted this. That does not address, however, the question you raise, which is, have materials changed so much in the 20 years since then that previous findings have been invalidated? I would guess no, but the fact is, we simply don't know, unless someone has got an awful lot of great information up his sleeve that he isn't publishing. Considering how expensive it would for any company to research this matter adequately, I am inclined to believe that the research has not been done. But I don't know that for a fact.

>... All of this contributes to the overall swell, porosity, and fixability of a coating.

Has anyone studied how this might affect image permanence? Note that Zawadzki and Dickerson tested the new emulsions from Kodak and found that functionally they were similar to the old ones, in that development times did not change significantly.

>You cannot fix well at all in a potassium hypo solution.

You will recall how that discovery in the 1930s led Edith Weyde to her discoveries in diffusion transfer photography, a topic I very briefly note in my book.

>I have no objection to the use of alkaline fixes except for the fact that you substitute the odor and pulmonary problems of acetic acid for the problems of ammonia, neither of which are not friendly to lungs.

That is an excellent point. The pH has to be controlled very carefully to make the product usable. Please note that because of the evolution of ammonia fumes, the simple alkaline fixer I published in FDC is recommended only for films in closed tanks.

>My fix is formulated to eliminate both odors, acetic acid and ammonia.

That is truly desirable. Personally, I would prefer some ammonia odor in exchange for the drastically reduced washing times. Others will, as you say, prefer a truly odorless fixer and it is unquestionable that the pH neutral odorless fixer which does not evolve fumes is safer in open trays in the typical darkroom.

>Historically, ammonia fumes have been found to be much more toxic than acetic acid fumes all things being equal

I don't think that can be argued.

>If you don't like using thiourea or thiocyanate, then just use plain ammonium hypo (60%) at 200 ml / liter and ammonium sulfite at 10 g/l adjusted to pH 6.5 with 28% acetic acid. Use a slightly longer wash time than with TF4 or use a hypo eliminator.

I object to this only on the grounds that I believe it is well established that the wash time, sub-alkaline, is not just slightly longer, but dramatically longer, and I encourage you to test this; I would also point out if it really is true that thiourea improves image stability, then why shouldn't we use it? Now I realize that much of what Ilford has had to say about fixers has not been accepted by the Kodak community by and large. Part of that is due to the Not Invented Here syndrome, but part of it is simply that Kodak had about a million more and largely better scientists. I would like to know if you or anyone else at Kodak investigated thiourea in this respect, and what your conclusions were. That is to say, not in its capacity as a fixer accelerator, but in its capacity as an archival stabilizer when used as a constituent of fixers.

>Now, please take note of this. It is finally time for me to bring this to the attention of everyone! I recommended 28% acetic acid,

I did see that clearly, Ron, and I really appreciate it. I should have said so explicitly, and I apologize for that. My comments were really in reaction to the previous thread, and though that is blessedly closed, there does seem to have been some 'carryover', if you will permit the use of the term in this context.

>While we're at it- why do we need a fixer that works in less than 5 minutes? .... I would rather go slow and make sure I did it right, than hurry up and get @#%$^- up negatives.

That's a good point: that accelerated processing as we know it today does demand more attention and intervention than conventional processing.

But our rapid processing procedures are unnecessarily messy. There are ways to accomplish rapid processing more easily from the user's point of view. My favourite paper patent is one of Haist's. The paper has a mercaptan-based monobath incoroporated into the paper. After exposure, you merely process it in plain sodium carbonate for a minute, and wash for a few minutes more. It is now developed and archivally fixed. That's all there is to it. You are never in contact with any chemical other than the carbonate. This patent has now expired and, according to Haist, the paper can be (and has been) made in a lightproof garage with ordinary wallpapering tools. The patent is referenced in vol. 2 of his book. I do wish someone would make the stuff!

> ... if my math is right (check it!), Indicator Stop Bath is about 84-87.5% acetic acid, a far cry from 28%.

Your math is correct. According to a recent MSDS, the product s 85-90% acetic acid, 10-15% water, <0.1% Bromocresol Purple. That is a surprise to me; I had always assumed it was 28%. The MSDS further states that the vapors are flammable above merely 108 degrees F, not an unheard of temperature in summer darkrooms. Goggles and a face shield are recommended, also a NIOSH Acid-gas respirator; just the VAPORS my cause burns; repeated exposure "may cause pharyngeal edema, Chronic Bronchitis, etc."

>Changing topics, I question how much of the "old" research on fixing and washing is valid on "new" materials, and how much difference there is between manufacturers.... [All prints] show similar deterioration, a bit of yellowing, and physical damage they've picked up. The process didn't seem to make much difference.

Taken on its face, that might seem to indicate that environmental factors could have more weight than processing factors. If so, it would be scary. In any case, I don't think the question is really, "how valid is the old research on new materials", but rather, "how valid is the old research period?" although I may be missing the point on that one.

The answer is, nobody knows much. Take the question of the film base. It was bedrock science for decades that cellulose nitrate degraded vastly more quickly than cellulose acetate. But research in the 1990s showed that science was wrong, and the acetate base can actually degrade faster in some collections. (P. Z. Adelstein, J. M. Reilly, D. W. Nishimura, and C. J. Erbland, "Stability of Cellulose Ester Base Photographic Film: Part I Laboratory Testing Procedures," Journal of Society of Motion Picture and Television Engineers, 101, 5:336-346, May 1992.) (There was similar surprise when some acetate-based 78 rpm sound records turned out to have a greater than 30 year life. The late Institute of Sound in New York was founded in the 1960s by Richard Stryker primarily to address that problem.)

>my early RC prints on Kodak paper have held up better than my fiber prints of similar age.

Could that be due to better washing, or to some other factor?

>Has anybody done any verification of [W.E. Lee's] work? Has this been update to relate to films and papers used by the average photographer?

No. There was inadequate funding to pursue it further. I spoke to Lee years ago about this and he wouldn't and probably couldn't say much beyond what he had published. If anyone else has done any substantial research, I am not aware of it. The unexpected death of Klaus Hendriks, perhaps the primary instigator of concern in this area, was an enormous blow. He was an effective noisemaker.

>I've heard that alkaline solutions premote "grain clumping". How does this effect apply to the "all alkaline processing" philosphy of todays developing trend?

The traditional wisdom that alkaline solutions promote grain clumping means only this: that relatively more alkaline developers will tend to produce more grain clumping than relatively less alkaline developers. In other words, development in D-76 will produce less clumping than development in DK-50. Haist suggests that the problem may not be so much the actual pH, but the time of development and degree of contrast. To minimize grain clumping, exposure and development must be at the possible minimum. However, "some alkalis, such as sodium hydroxide, appear to have a disintegrating effect on the gelatin of the emulsion layer. This action gives the silver particles a greater chance to come together to form clumps, thereby increasing graininess. Developing agents requiring the stronger alkalis may become associated with the production of grain, even though some of this may be due to the action of the alkali." (Haist, v. 1, p. 395.)

All practical film developers have a pH of at least 8. It would seem that fine grain development is usually achieved within the range of pH 8 to 9. For reasons which have never been satisfactorily explained, a borate buffer system seems to much more photographically effective in securing a high quality fine grain image than a carbonate/bicarbonate system of equivalent pH. Alternate buffer systems, although attractive, are, according to Zawadzki and others, much too expensive to be practical.

In any case, grain clumping, so far as we know, is only affected by the alkalinity of the _developer_ solution, not by any other part of the processing cycle. However, there are some assumptions here. (1) Alkaline post-development processing will occur at around pH 10 if any of the solutions require glutaraldehyde hardening; alkaline post-development processing will occur at pH 8-10 when hardening is not required. If, for some reason, alkaline post processing were to occur at a very high pH, i.e. that of sodium hydroxide, then there might be some potential for damage.

>You won't stop, will you.

Well, if I've expressed myself so badly that you still don't get the point, I feel I must try harder.

>"And you still don't understand why photographic manufacturers don't like to let glacial acetic acid into photographers' hands?"

>------ As noted above my myself and Terry Stedman, Eastman Kodak sells glacial acetic acid in 1 gallon and 6 x 1 gallon size quantities.

But Ron: that's just the point: 1 gallon glacial acetic acid is intended not for _photographers_ but for _labs_. There's a century of manufacturing wisdom behind the practice of selling 28% acetic acid to _photographers_. Why argue with one of the industry's first real efforts to make the _photographer's_ darkroom safer? Leave the more dangerous chemicals to lab technicians who should know how to handle them.

>As noted by Patrick Gainer, he has accidentally aspirated some into his mouth and survived intact. As noted by Anders Brathe, acetic acid is a weak acid and is far weaker than sulfuric and far less damaging to human tissue than common lye sold in supermarkets.

Right. But Kodak's toxicologists believe (as they told me today) that if you swallow glacial acetic acid, you will likely die, because your oesophagal tract will have been burnt out. Who's right? Patrick, fortunately, didn't swallow. Shall we ask him to try it again? And while we're waiting to find out what happens, should we be encouraging people to treat glacial acetic acid as an aspirable chemical? Is that really in the best interests of the public?

>...you probably don't have sufficient chemistry background ... you seem to completely misunderstand the difference between a strong and a weak acid

Ron, I don't know how you get there just because I point out that the 28% acetic acid common sold to _photographers_ is much safer than the glacial acetic acid commonly sold to _labs_. Does Haist have an insufficient chemistry background because he spent a page pointing this out? Did Crabtree and Matthews have insufficient background because they too spent a page pointing this out?

>Did you ask the toxicology department at EK about any other chemicals?

No, because I thought we were discussing acetic acid.

>I have worked with the toxicology department at EK several times when we were working with new chemicals, so I am quite familiar with their work and responsibility at EK.

So give 'em a call!

>Alkaline hypo merely allows maximum swell for maxiumum diffusion outward which allows shorter wash times under some circumstances with some products.

That is deeply misrepresentative of the facts, Ron, because it does not account for the fact that, with alkaline fixing, you have an almost an order of magnitude less washing time. Alkaline post processing of acid-fixed prints doesn't get you anywhere near that level of success. Let me suggest again that you read Green and Rumens, J. Phot. Sci. 19:149-150 (1971). Or don't they have adequate chemistry background?

>No simple statement can answer all of these factors. I believe in what Al Weber and Dave Vestal suggest.

Then let me quote what David Vestal wrote about my TF-4 alkaline fixer in the March/April 1993 issue of Darkroom & Creative Camera Techniques, pp. 42-67:

"I ordered TF-4 for testing with some skepticism, mostly because of experiences with unhardened prints that were too soft physically to survive. However, the test measurements show that TF-4 is effective, and this time the print emulsion was not disturbingly soft [as it had been with Ilford's fixer]. It changes print processing and takes some getting used to, but it also shortens washing times and saves water. No acid stop bath is used with TF-4, and no washing aid."

Now Ron, if you'll put aside pride, and, as I suggest, reformulate your fixer to pH 8 or 9 -- I can suggest a suitable buffer system if you'd like -- I believe you will find that washing times are reduced by about an order of magnitude for film. The improvement for paper will be less, but will still be substantial. This simple alteration in your formula will cut down total processing time dramatically, and result in substantial savings of water. Put it this way: by supercharging ammonium thiosulfate, as you suggest, you can reduce fixing time from perhaps 2 minutes to 1. But only by alkalinizing the solution will you be able to cut down washing times in a really dramatic fashion. Film will be washed to archival levels in under 60 seconds; paper washing times will be reduced to about one third what they would be with the formula as presently published. It _is_ total processing time that we're interested in, here, isn't it?

Finally, have you tested for the paper softening Vestal was so concerned about in non-hardening paper fixers?

and a couple of other footnotes:

> Another thing not generally known is that thiocyanates and thiourea are much more stable than hypo. Therefore it is theoretically possible to design a fix that does not decompose if you just leave out hypo and use thiourea and a thiocyanate. Wow, a fix that does not sulfurize.

Thiosulfate is only unstable in acid solution.

> read the MSDS as Lex suggests

but an MSDS usually contains the legally minimum information. More useful information will be obtained from a trained toxicologist at a poison control center. For example the MSDS does not have to tell you that exposure to ammonium thiocyanate may cause thyroid damage, but the toxicologist will be able to tell you that.

Finally, to anyone whose priority is saving time, the important thing is less the length of fixing time, than the length of the washing time. As long as the fixer contains any thiosulfate, there is only one way to dramatically reduce washing time: use it at alkaline pH.

May I suggest this simple test, Ron? Test washing times for your fixer as formulated; then comparison test washing times with your fixer reformulated to a pH around 9. You will find that washing times for both films and paper are approximately an order of magnitude less when you reformulate so that the fixer is alkaline. Have a look at Green and Rumens, J. Phot. Sci., 19:149-150 (1971). As the date indicates, this information has been publicly available for over 30 years. You will now have a fixer that both fixes rapidly _and_ washes rapidly.

To Ed: the Ilford rapid fixing system of circa 1980 was never accepted by Kodak, one reason being that it didn't work on Kodabromide paper. The theory depends on the fixer being able to clear the paper in under 10 seconds. As Ron has pointed out, there will be tremendous potential consistency problems at such short times. I do not remember anyone at Kodak making that explicit point to me, but I am certain that Ron is absolutely correct on this point. But that is only one problem. Papers have evolved since such that they can no longer be cleared in 10 seconds. Clearing times in fresh film-strength ammonium thiosulfate fixer are now more often greater than 30 seconds. Yet the Ilford system, considerably modified, still survives. I think we have to accept that Mason probably erred when he ascribed the system's initial success to short immersion times such that thiosulfate cannot bind to the paper fibres.

IF rapid, archival washing of films and papers is your goal, the only practical way to achieve it is through alkaline fixing. There is always the attractive possibility of eliminating thiosulfate altogether. But since W.E. Lee's disturbing papers showing that a very small residual amount of thiosulfate can have a stabilizing effect on b/w materials, there has been more reluctance to work with thiosulfate substitutes.

>End of discussion.

Ron Mowrey<

Not without a postscript from Kodak's toxicology department, which can be reached 24 hours and is an invaluable resource.

Acetic acid greater than 20%: causes severe skin and eye burns; vapor is very irritating to eyes and respiratory system; may be fatal if swallowed.

Acetic Acid at 15-20%: causes skin and eye burn [note that 'severe' is no longer a characterization].

Acetic Acid at 5-15 %: can still cause eye burns but the skin characterization goes down from 'burn' to "irritation".

Acetic Acid at 1-5%: can cause eye irritation.

Ammonium thiocyanate has been shown to cause thyroid damage in humans.