Odd Pyro Negative Problem

[Steve Hamley]

Folks,

Also posted on LFF...

I recently did a nice little 4x5 image on B&W developed in PMK that I printed up on platinum nicely and made multiple prints. I got the bright idea that I would take a post-it note with the printing info and place it on the sleeve the negative was in, a single neg Kodak-style sleeve.

I did not file the neg, but left it out not far from a large window, albeit with modern UV screening glass. There is no discernible mark or shadow on the negative visible to the eye, stain or silver, but you can see where this is going.

In spite on being unable to see any artifact whatsoever on the negative, by sky, bare bulb, bright wall, etc, the shape of the post-it prints on the platinum paper clearly with about 1/2 stop less density, in other words, the rest of the negative has lost some density to UV, even though you can't see it.

So what to do about it. What I've come up with so far thinking about and talking to Don D. is this.

1. Refix and wash in strong hypo clear. Dry and print

2. Use acetic_sodium sulfite to remove some of the stain. Dry and print.

3. Lay the neg out and hope exposure evens it out, or place it under my plate burner for 5 - 10 minutes and see if that makes any difference.

So any ideas?

Cheers, Steve

 

[Gerald C Koch]

Pyro developers leave a stain image, the stain is actually a dye. Some dyes are bleached easily by exposure to strong light. It doesn't have to be UV light. I am afraid that the negative is ruined. Perhaps you could scan it, photoshop it and make a new digital negative.

 

[Ian Grant]

Your best bet is no 3, leave the negative in similar light to before but for quite a bit longer. it may even up.

Ian

 

[Photo Engineer]

And this is a potential problem with pyro negatives. They can fade!

I'm sorry to hear this, but I agree with Jerry. Fade is the reason for the problem.

PE

 

[john_s]

Thanks for letting us know, Steve. I often leave things on my desk for quite a while, and most of my negs are dev'd in pyrocat, which presumably would be similar. I had been under the impression that the stain was very robust (though able to be removed chemically).

 

[Steve Hamley]

Thanks everyone,

Keep in mind I can see nothing whatsoever in the negative by eye with any light source - that's the odd thing.

I guess I can make a mask from a "dead" print and either lay it out for a few weeks, or pop it under the plate burner for a few minutes to see.

Cheers, Steve

 

[Photo Engineer]

You could bleach out the entire pyro image, then bleach the silver image in a Ferri rehal bleach and redevelop in a pyro developer. This would presumably restore the original image with the pyro mask intact. Just a theory until you try it.

PE

 

[Steve Hamley]

Thanks PE,

That's the doomsday scenario, but it should be an interesting experiment.

I'll post result, but of course it may be a while.

Cheers, Steve

 

[M. Lointain]

I have a similar neg with a pyro streak (Pyrocat) and have been wondering what I can use to bleach out the stain. Don't want to hijack the thread, but I have no idea what acetic_sodium sulfite is. Do you mean Acetic Acid as one possibility and Sodium Sulfite as another? What is used to bleach a pyro stain?

 

[Steve Hamley]

Per Gordon Hutchings "Book of Pyro",

1/2 ounce of 28% acetic acid and one teaspoon sodium sulfite per quart

Cheers, Steve

Don't want to hijack the thread, but I have no idea what acetic_sodium sulfite is. Do you mean Acetic Acid as one possibility and Sodium Sulfite as another? What is used to bleach a pyro stain?

 

[Ian Grant]

I have a similar neg with a pyro streak (Pyrocat) and have been wondering what I can use to bleach out the stain. Don't want to hijack the thread, but I have no idea what acetic_sodium sulfite is. Do you mean Acetic Acid as one possibility and Sodium Sulfite as another? What is used to bleach a pyro stain?

The Pyro stain is fairly stable with Pyrocatechin based developers and will withstand quite aggressive bleaching, and in addition because of the tanning (hardening) effects of the developing agent any bleaching of the stain itself runs a high risk mof being uneven and blotchy.

Something that's not been raised is the effects of incomplete dye fornmation, these would potentially be unstable and more prone to effects of light etc and somethingsimple like choice of fixer might have a major impact here, a regular fixer with a pH of 5.2 to 5.4 may be more beneficila than a neutral pH7 or alkali fixer.

Ian

 

[M. Lointain]

Thanks Steve, that clears it up.

Ian, how would you recommend bleaching a pyrocatechin stain? I really want to save the aforementioned negative.

 

[Steve Hamley]

Thanks all, especially PE, Ian, and Gerald.

Now let me ask another question, since there's absolutely nothing visible on the negative by eye with any visible light source, do you think that printing via enlarger or on silver chloride (Azo, Lodima) with a tungsten bulb might work? I can't test just yet.

Cheers, Steve

 

[Ian Grant]

Thanks Steve, that clears it up.

Ian, how would you recommend bleaching a pyrocatechin stain? I really want to save the aforementioned negative.

I doubt you can, instead you'll need to retouch the prints. I found that the pyrocatechin stain is quite resilient to the bleaches I've tried, the OP was asking about Pyrogallol stain and it;s slightly different.

Ian

 

[Photo Engineer]

Using an enlarger or Azo paper with a UV absorber might help and give you a good photo. No way to find out but try..

Best of luck.

PE

 

[Steve Hamley]

Thanks PE,

Sometimes I think photography isn't about taking pictures, it's about solving problems. I appreciate your advice.

Cheers, Steve

 

[Gerald C Koch]

I think this unfortunate cicumstance points out the problem of using a developer that has not been thoroughly tested. Just because many people have used this developer does not mean that all its kinks have been discovered. Commercial developers have been exhaustively tested under various conditions. Often it is the case that more man-hours are spent in testing than in the initial development of a product.

The english painter Joseph Turner known for his watercolor prints was one of the first to use pigments made using the (at that time) new synthetic aniline dyes. Now much of his work can only be viewed at the British Museum in very dim light for a few minutes at a time. The dyes were untested and had not been used long enough for anyone to notice the problem.

 

[Steve Hamley]

In all fairness to PMK, at this point we really don't understand what's going on, or if the issue would occur with other developers, commercial or not. ??

Cheers, Steve

 

[Photo Engineer]

These dyes like all dyes will fade in time! Silver will not.

PE

 

[Gerald C Koch]

In all fairness to PMK, at this point we really don't understand what's going on, or if the issue would occur with other developers, commercial or not. ??Cheers, Steve

On the contrary we do know what is going on. All dyes are subject to fading, some more rapidly than others. From the OP's sad experience he has shown that the stain image produced by PMK is not stable toward light. This problem will be the same for all stain developers whether they use pyrogallol or catechol. Developers that produce only a silver image will not have this problem. People need to be aware of this problem and protect their negatives from strong light.

 

[Ian Grant]

I think this unfortunate cicumstance points out the problem of using a developer that has not been thoroughly tested. Just because many people have used this developer does not mean that all its kinks have been discovered. Commercial developers have been exhaustively tested under various conditions. Often it is the case that more man-hours are spent in testing than in the initial development of a product.
.

While PMK may not have been tested by a major manufacturer many staing developers have been, after all most companies sold Pyrogallol or Pyrocatechin based developers over a long period of time,including both Ilford & Kodak. It needs to be remembered that some non pyro developiers also have a slight staining action.

There is evidence that with PMK negatives that initial exposure to UV light has a very small effect on the staining causing a very slight loss in density but that the negatives stabilise and there's no further density loss and no significant effcet on the printability. This was why I suggested the OP in Post #3 of this thread "Your best bet is no 3, leave the negative in similar light to before but for quite a bit longer. it may even up."

Ian

 

[Photo Engineer]

On the contrary we do know what is going on. All dyes are subject to fading, some more rapidly than others. From the OP's sad experience he has shown that the stain image produced by PMK is not stable toward light. This problem will be the same for all stain developers whether they use pyrogallol or catechol. Developers that produce only a silver image will not have this problem. People need to be aware of this problem and protect their negatives from strong light.

Jerry;

You and I are in total agreement on this. It is as simple as the statement "All Dyes Fade". I have stated this before over and over and it is the reason why I do not use staining developers. In fact, it is probably why Kodak never really sold staining developers.

I'm just surprised that we have not seen more complaints to this effect.

PE

 

[Ian Grant]

In fact this thread is the first I've really heard of the issue. Intuitively we know dyes are not infinitely stable, but since we always read the stain is "permanent", I guess most people assume it is permanent enough so that the printing properties of the negative will not change over its reasonable "print life" (I mean, does a negative realistically need to outlast its printer?). This thread, however, points to stained negatives potentially having significantly lower stain stability than I had ever considered. A little scary.

I'm wondering why, for example, a guy like Alan Ross hasn't noticed this when printing any of Adams's older stained negatives. Or maybe he has and hasn't written about it. Or maybe it's that Adams's negatives are so carefully stored.

Anyhow, very interesting discussion here. I rarely use staining developers anymore, but I'm still intrigued by this.

Ansel Adams negatives are not subjected to UV light during printing so it's unlikely there would be an issue.

There seems to be no issues with pyro negatives which have been used to make many contact and platinum prints either so there's a bit of speculation going on based on thin air about it being a potentially serious problem.

So there's a need for realism, Pyro negatives have lasted well over 100 years with no issues of the stain fading significantly. yet colour negatives, transparencies and prints do fade relatively quickly, 1950's Kodachromes are washed out, early Kodacolor prints sufferd similarly. Even E6 slides fade significantly with projection nad RA4 prints when displayed in well lit areas..

So put in context Pyro negatives last remarkably well even when exposed with UV light sources for alternative processes.

Ian

 

[Photo Engineer]

The simplest analog of the stain created by Pyro developers is Quinhydrone which was used in green ink for many many years. It is made from Hydroquinone. It fades. At present, I know of no study that has been undertaken to verify the light stability of stained negatives. All we have is subjective evidence. At this time, our evidence is only the "pattern" observed in the OP.

PE

 

[Steve Hamley]

Hey guys,

I'm not arguing that nothing ever faded with respect to all wavelengths. Undoubtedly it did with respect to UV only!! Hence my question, qualified that there was no visible difference in stain or silver.

I also understand that stains can fade, however, might it be reasonably expected that it would be visible?

All developers. films, fixers, cameras, and lenses have shortcomings. I'm not arguing that. I just want to understand what's going on with respect to fixing the issue of a single negative if at all possible.

Cheers, Steve