Stop Bath.. How important?

[Sirius Glass]

Case A in Control Theory is called Bang Bang Control and is more energy efficient than Plan B.

What is meant by the term "efficient"?

Least energy useage.

 

[Sirius Glass]

Would you (the global you, not the Blockend you) rather spend 30 seconds stopping development with cheap diluted (Thanks David Lyga) stop bath or 2 minutes fussing with multiple water changes? Let's assume you live in Arizona where water will soon become precious.

I live in a region where water conservation is important and I use stop bath. The only reason I see not to use stop bath, other than a specific developer requiring only water be used as stop bath, is that stop bath especially with indicator is just so damned expensive!

 

[faberryman]

Film photography is all about fussing with liquids. Unless you can afford to send everything to a lab and professional printer, of course. People who consider the process convoluted, migrated to digital imaging years ago. Only the fussers are left, and we revel in it.

What is convoluted about film developing? It seem to be a pretty straight forward process. No alchemy involved. Nothing has changed in the 45 years I have been at it. Sure, film stocks have improved, and there have been a couple of new developers introduced, but the old ones remain popular and continue to work fine. Develop, stop, fix, wash. Couldn't be simpler. Of course, any idiot can make something simple complex.

 

[blockend]

What is convoluted about film developing? It seem to be a pretty straight forward process. No alchemy involved. Nothing has changed in the 45 years I have been at it. Sure, film stocks have improved, and there have been a couple of new developers introduced, but the old ones remain popular and continue to work fine. Develop, stop, fix, wash. Couldn't be simpler. Of course, any idiot can make something simple complex.

..but more complicated than taking an SD card out of a camera. Plus there are temperatures to be taken and colour negative, black and white negative and colour transparency processing times to adhere to. I'd compare it to cooking. Easy when you know how and which rules can be broken, but a steep learning curve nonetheless.

 

[faberryman]

..but more complicated than taking an SD card out of a camera. Plus there are temperatures to be taken and colour negative, black and white negative and colour transparency processing times to adhere to. I'd compare it to cooking. Easy when you know how and which rules can be broken, but a steep learning curve nonetheless.

It is not a steep learning curve. Follow the instructions.

 

[alanrockwood]

I use a phototherm for processing my black and white film. It is an automated rotary processor that uses a water "stop" bath. I have never noticed a problem arising from the use of water as a stop bath.

Other than the original poster, who mentioned that on the long edges of each frame there is a subtle area of increased density which runs the length of the frame (not specifying whether the defect was in the border or extended into the image), has anyone else seen any defect in development arising from the use of water instead of an acid stop bath?

 

[MattKing]

I use a phototherm for processing my black and white film. It is an automated rotary processor that uses a water "stop" bath. I have never noticed a problem arising from the use of water as a stop bath.

Other than the original poster, who mentioned that on the long edges of each frame there is a subtle area of increased density which runs the length of the frame (not specifying whether the defect was in the border or extended into the image), has anyone else seen any defect in development arising from the use of water instead of an acid stop bath?

Do you re-use your fixer, or do you use it "one-shot"?
A significant part of the advantage of using Stop Bath relates to how it impacts other steps in the entire process.
It isn't necessarily a "defect" or "no defect" analysis. It is more an analysis of whether there are advantages to using Stop Bath, particularly for those who either:
1) don't have the advantages of mechanized processors; or
2) for those who have the advantage of mechanized processors, but have a need to maximize through-put, consistency and economy.
As an example of one such analysis, as Stop Bath is relatively speaking so cheap, and use of it tends to extend the life of fixer that is intended for re-use, it may very well more than pay for itself.
I am comfortable with following the suggestions of Ilford and Kodak (the chemicals I use). If you look at a bunch of the Kodak datasheets there are very few references to using running water with film, and way more references to using stop bath with film.
There are no references therein to using non-running water.

 

[alanrockwood]

Do you re-use your fixer, or do you use it "one-shot"?
A significant part of the advantage of using Stop Bath relates to how it impacts other steps in the entire process.
It isn't necessarily a "defect" or "no defect" analysis. It is more an analysis of whether there are advantages to using Stop Bath, particularly for those who either:
1) don't have the advantages of mechanized processors; or
2) for those who have the advantage of mechanized processors, but have a need to maximize through-put, consistency and economy.
As an example of one such analysis, as Stop Bath is relatively speaking so cheap, and use of it tends to extend the life of fixer that is intended for re-use, it may very well more than pay for itself.
I am comfortable with following the suggestions of Ilford and Kodak (the chemicals I use). If you look at a bunch of the Kodak datasheets there are very few references to using running water with film, and way more references to using stop bath with film.
There are no references therein to using non-running water.

I re-use the fixer. All other solutions are one-shot.

As I mentioned, I use water in my phototherm. That is what the standard phototherm program does. In principle it would be possible to use acid stop bath, but to do so would require buying a new chip with a new program burned into the ROM. The cost for a new chip is (was) $100, but I don't know if that service is still available since phototherm has discontinued their film development products and transferred support to a private individual. Also, this change would require using the stop bath on a one-shot basis, since the standard phototherm only allows the saving of one solution, and from an economic standpoint it makes more sense to save the fixer. (The "super" models allow the saving of two solutions I believe.)

 

[faberryman]

I re-use the fixer. All other solutions are one-shot.

As I mentioned, I use water in my phototherm. That is what the standard phototherm program does. In principle it would be possible to use acid stop bath, but to do so would require buying a new chip with a new program burned into the ROM. The cost for a new chip is (was) $100, but I don't know if that service is still available since phototherm has discontinued their film development products and transferred support to a private individual. Also, this change would require using the stop bath on a one-shot basis, since the standard phototherm only allows the saving of one solution, and from an economic standpoint it makes more sense to save the fixer. (The "super" models allow the saving of two solutions I believe.)

Well, if you can't use stop bath when processing film, then it follows that you wouldn't use it. Do you use stop bath when you print?

 

[alanrockwood]

Well, if you can't use stop bath when processing film, then it follows that you wouldn't use it. Do you use stop bath when you print?

I am not set up for wet-lab printing these days.

 

[MattKing]

I re-use the fixer. All other solutions are one-shot.

As I mentioned, I use water in my phototherm. That is what the standard phototherm program does. In principle it would be possible to use acid stop bath, but to do so would require buying a new chip with a new program burned into the ROM. The cost for a new chip is (was) $100, but I don't know if that service is still available since phototherm has discontinued their film development products and transferred support to a private individual. Also, this change would require using the stop bath on a one-shot basis, since the standard phototherm only allows the saving of one solution, and from an economic standpoint it makes more sense to save the fixer. (The "super" models allow the saving of two solutions I believe.)

In essence, the Phototherm people have done the analysis for you .
Of course, they also had the ability to design an effective running water rinse before fixer into their excellent machines.
If I had a Sidekick - and even though it wouldn't make sense given my through-put, I would like one - I would be quite comfortable relying on that running water rinse.
But I do think that when discussing the issue in general, before an audience that includes a majority of people who use hand inversion tanks, it is better to talk about relative benefits of using stop bath vs. water rinse. And vice versa.

 

[faberryman]

I am not set up for wet-lab printing these days.

So if you can't use stop bath in your film processor and you don't print, it sounds like you don't really have a dog in the hunt in the stop bath debate.

 

[alanrockwood]

So if you can't use stop bath in your film processor and you don't print, it sounds like you don't really have a dog in the hunt in the stop bath debate.

I still process film, so I still have one dog in the hunt, and eventually I will set up my darkroom again for print processing, so I will have two dogs in the hunt.

 

[faberryman]

I still process film, so I still have one dog in the hunt, and eventually I will set up my darkroom again for print processing, so I will have two dogs in the hunt.

Except that you exclusively use a film processor that doesn't allow stop bath use.

 

[alanrockwood]

Except that you exclusively use a film processor that doesn't allow stop bath use.

In its standard configuration my processor uses water for a stop bath, which is all the more reason to be interested in the adequacy of using water as a stop bath. But honestly, I don't have to justify my interest in the topic to you, so let's just chock it up to my being interested in the topic.

 

[Sirius Glass]

If one does not use stop bath ask oneself why have photochemical companies invested so much money over decades doing research and development, setting up production lines and marketing to bring stop bath to market?

 

[alanrockwood]

Alan, here is an example suggested by Haist. A Metol and HQ developer is run directly through a good wash and then a neutral or alkaline fix. This leaves behind a substantial amount of HQ and Metol. The wash should remove it. However, due to solubility (remember how hard it is to dissolve Metol, even if it is the Sulfate salt??), Metol and HQ can be left behind. What is found in testing, is that Metol can be removed in a Stop, and HQ can be removed in a neutral or alkaline fix! This is barely the tip of the iceberg so to speak.

Anchell and Troop quote Ansel Adams on stops and then stated the pros and cons based on Adams positive position. Haist gives details of tests by Henn and Crabtree related to uniformity and devotes about 20 pages to stops.

PE

I would like to be able to read what Haist wrote on this topic, as well as what Henn and Crabtree wrote. Do you have the references?

Also, if Metol is left behind, does it persist into the developed film or final print itself? If so, what effect does it have on image quality or image stability in the film or print?

 

[Photo Engineer]

It will take me some time to do it. He shows a plot of HQ retention and discusses other problems with chemical retention. I thought I marked it, but apparently not.

PE

 

[alanrockwood]

It will take me some time to do it. He shows a plot of HQ retention and discusses other problems with chemical retention. I thought I marked it, but apparently not.

PE

I am an emeritus faculty member at the University of Utah. As such, I have library privileges, so if I have the references I can probably consult the original works, assuming the library has them in its collection.

 

[Photo Engineer]

The book (Vol. I) is on my lap right now. Been searching.

PE

 

[Photo Engineer]

OK, here it is. VII P 204. I had to go through VI until I got to it in VII. I don't keep track of these things. Sorry. In the graph on this page and the brief associated discussion, Grant is testing hypo retention in monobath processing. He and others (cited in the discussion by Haist) find that hypo washes out just fine, but surprisingly HQ does not. There is no easy test for Hypo or Metol and Metol should actually be worse. So, my work went on to find if PPDs were retained. Boy, howdy, were they. PPDs caused pink stain in color materials if there was not an acid stage to extract them.

The bottom line is that a water stop may work but must be running water or acid. This is true for B&W and color. This is old history to me from about 1969, where we found the problem in color and I was called back from Christmas vacation to work on it for color paper, namely Ektaprint 3.

Yes, developing agent is a problem and can cause brown stain in B&W and pink stain in color. There is more than this short note can express.

Hope this helps.

PE

 

[alanrockwood]

OK, here it is. VII P 204. I had to go through VI until I got to it in VII. I don't keep track of these things. Sorry. In the graph on this page and the brief associated discussion, Grant is testing hypo retention in monobath processing. He and others (cited in the discussion by Haist) find that hypo washes out just fine, but surprisingly HQ does not. There is no easy test for Hypo or Metol and Metol should actually be worse. So, my work went on to find if PPDs were retained. Boy, howdy, were they. PPDs caused pink stain in color materials if there was not an acid stage to extract them.

The bottom line is that a water stop may work but must be running water or acid. This is true for B&W and color. This is old history to me from about 1969, where we found the problem in color and I was called back from Christmas vacation to work on it for color paper, namely Ektaprint 3.

Yes, developing agent is a problem and can cause brown stain in B&W and pink stain in color. There is more than this short note can express.

Hope this helps.

PE

Thanks. I will try to find the book in our university library and read more about it.

 

[removed account4]

Also, if Metol is left behind, does it persist into the developed film or final print itself? If so, what effect does it have on image quality or image stability in the film or print?

I'm probably wrong because I'm not a Photochemist, but ... I did lab work for someone who processed her films for 60 years before I met her without Stop Bath, and her negatives from the late 20s early 30s looked as pristine as the negatives from the 1980s. If Metol or HQ didn't wash out of the film wouldn't her negatives shown there were problems 60+ years later? ... Maybe because her film was stored in glassine, in envelopes in a filing cabinet, out of sunlight and UV contamination, her Metol/HQ contaminated films never presented problems.
Thanks !
John

 

[alanrockwood]

OK, here it is. VII P 204. I had to go through VI until I got to it in VII. I don't keep track of these things. Sorry. In the graph on this page and the brief associated discussion, Grant is testing hypo retention in monobath processing. He and others (cited in the discussion by Haist) find that hypo washes out just fine, but surprisingly HQ does not. There is no easy test for Hypo or Metol and Metol should actually be worse. So, my work went on to find if PPDs were retained. Boy, howdy, were they. PPDs caused pink stain in color materials if there was not an acid stage to extract them.

The bottom line is that a water stop may work but must be running water or acid. This is true for B&W and color. This is old history to me from about 1969, where we found the problem in color and I was called back from Christmas vacation to work on it for color paper, namely Ektaprint 3.

Yes, developing agent is a problem and can cause brown stain in B&W and pink stain in color. There is more than this short note can express.

Hope this helps.

PE

As you noted, the figure on p. 204 of volume 2 deals with monobath processing. Presumably similar principles would apply more or less to conventional processing. For those who don't have access to the book I am posting a scan of the page as other readers may find it helpful.

As shown in the figure and also noted in the text on p. 203 it takes about 40 seconds to remove the thiosulphate using cold tap water (12 degrees C, which is about 54 degrees F). It takes a little longer, about 60 seconds, to remove the hydroquinone in order to prevent staining. Presumably it could be a little faster at higher temperature, but he does not address that issue.

In the chapter on stop baths (chapter 12 of volume 1) Haist says (pp. 539-541) that a water stop bath is fine if the developer is a weakly alkaline slow acting developer but recommends acid stop bath if using a highly alkaline highly buffered rapid acting developer in order to prevent uneven development or image non-uniformity. No studies or data are given to support that recommendation, nor does he say why uneven development could happen if a slow-acting stop bath like water is used. Also, he doesn't give us examples of development solutions would fall into the low-alkalinity slow-acting category or that are highly-alkaline rapid-acting developers, so it is hard to know where the dividing line would be. (The dividing line between the classes is probably not sharp anyway.) My guess is that something like D-76 would fall more toward the slow-acting category, depending on the concentration and temperature but I don't know for sure what Haist meant.

Concerning metol in relation to stop baths, I don't believe metol is mentioned in the chapter or stop baths. At least I can't find any index entries for metol that refer to the page numbers within the chapter on stop baths.

Haist does mention that one effect of using a water stop bath is that it can act as the second bath of a two-bath developer. Presumably this could enhance adjacency effects and/or enhance the tendency of compensation in the development phase. Obviously, this could be considered either desirable or undesirable, depending on the preferences of the photographer.

 

[Photo Engineer]

Well, one thing observed is that if a water rinse is like the second bath of a 2 bath developer, it is then not useful to reuse it. It should either be dumped right away or be one consisting of running water.

As for Metol not being mentioned, that is where I come in. Note my comments above about PPD being retained in color processes. A process with a stop or an acid stabilizer extracts the PPD from the coupler droplets. I have the advantage of having talked to Grant about this and other problems and know that Metol is very hard to remove from coatings without an acidic extraction of some method. I mentioned all of this before.

Remember that this work of Grant's was done while he worked at EK and was heavily redacted. There were internal reports on this subject, but he had to go to an external report and use that report and rely on others to generalize what might happen if you did not have an all alkaline process.

This is a very difficult subject with many different views having been expressed. I have used both, when there was no acid present to make stop or some such. But, mostly I use a stop.

As for non uniformity, it goes up with format size and with paper vs film. Remember that this work was done in the age of fiber based paper supports and thicker film coatings.

The attached images are not properly identified. The first image is from Anchell and Troop. Sorry Steve, sorry Bill.

PE