Prescysol vs. pyro safety issues

[Jim Noel]

If you are worried about health and the environment, but still want to use a staining developer, check out this thread on APUG.

Commercial Coffenol manufacturer?

 

[rwyoung]

Did you know that human urine contains pyrocatechin?
...snip...

http://www.cmaj.ca/cgi/content/full/172/8/1002

 

[BobNewYork]

Damn! If I have to contract ochronosis to get away with a good night out - guess I'll just take my medicine like a man!

 

[Dave Miller]

John, you imply that you find that using staining developers requires more effort than using a non-staining one. Would you like to amplify, if that is indeed what you meant?
Ernie, the only reason that I use a staining developer (Prescysol) is that I find the negatives produced with it easier to print, requiring less burning and dodging than with other developers. It certainly doesn't convert a mediocre picture into a work of art, or inject emotion into the print; that's got to be done in camera surely.

 

[gainer]

Did you know that human urine contains pyrocatechin?

Pyrogallol and pyrocatechin (or catechol as some call it) aren't all that dangerous. Reasonable care mitigates the risks.

Hydroquinone is quite dangerous too. We use it without batting an eye.

And hydroquinone is also a staining developer. Use it in place of catechol in Pyrocat HD or MC and you'll see. Not the same color, but staining nonetheless.

 

[Uhner]

the only reason that I use a staining developer (Prescysol) is that I find the negatives produced with it easier to print, requiring less burning and dodging than with other developers.

Yes, that is also my reason for using a Pyro developer.

 

[jovo]

John, you imply that you find that using staining developers requires more effort than using a non-staining one. Would you like to amplify, if that is indeed what you meant?
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No, Dave, I didn't mean to suggest that staining developers are any more difficult to use than non-staining ones. I meant that, for me, the effort to "learn" a new developer and test it is not worth it.

 

[Trevor Crone]

the only reason that I use a staining developer (Prescysol) is that I find the negatives produced with it easier to print, requiring less burning and dodging than with other developers. It certainly doesn't convert a mediocre picture into a work of art, or inject emotion into the print; that's got to be done in camera surely.

Indeed, I would have to give a third nod to this.

 

[ernie51]

John, you imply that you find that using staining developers requires more effort than using a non-staining one. Would you like to amplify, if that is indeed what you meant?
Ernie, the only reason that I use a staining developer (Prescysol) is that I find the negatives produced with it easier to print, requiring less burning and dodging than with other developers. It certainly doesn't convert a mediocre picture into a work of art, or inject emotion into the print; that's got to be done in camera surely.

Dave, One reason for the staining approach is to allow me to be more productive in the darkroom. Less time spent in test prints etc.to reach satisfactory results would make my life easier. I also tend to shoot a fair amount of subjects of significant contrast so I anticipate some benefit here as well. Am I wrong in these assumptions?

 

[jovo]

Dave, I also tend to shoot a fair amount of subjects of significant contrast so I anticipate some benefit here as well.

If I'm not mistaken, contrast control is the principal strength of staining developers. In a magazine (perhaps it was View Camera) many years ago, there was an article by Gordon Hutchings about his pyro formula that included some of his photographs. They were made in conditions of extreme contrast and they were beautifully rendered. As a result, I bought the "kit" from Photographer's Formulary. After reading the book, I chose not to pursue the process, but I can certainly see why others did. I found other means to achieve the results I was looking for, but there's no doubt that staining developers achieve what they're touted to achieve.

 

[JBrunner]

In my experience the benefits of Pyro are twofold. The first benefit is holding detail in the highlights. The second benefit is having "two" densities in the same negative, enabling me to print silver, and still having enough contrast for pt/pd. I have had my best results in the second aspect with PMK, but that is also the Pyro developer I have the most experience with.

I purchase pre-mixed liquid A&B solutions, and wear nitrile gloves. The primary hazard of pyro is breathing the powder, which is avoided with the premixed solutions. The secondary hazard is dermal absorption, which is negated by the gloves. Follow those two precautions, and handle and store Pyro responsibly as you would any chemical, and you will be fine.

In perspective- if you get a little on you, wash it off and be more careful. That kind of exposure isn't going to harm you. OTO using it repeatedly without gloves over time can damage your kidneys and liver.

Pyro is a tool, and requires certain accommodations to use it to advantage. If you understand it, you can use it. It isn't a magic bullet, you have to be prepared for what it can give you, and expose and process accordingly. Without that understanding, it can be finicky and frustrating.
In regard to highlight detail, here is a scan of an 8x10 contact print. The negative was processed in PMK. The sun is in the shot, but was not obscured by clouds or anything else. The causeway remains in the water, in which the barest detail can be discerned in the print but not in the scan were 13 stops down from the sun.

 

[Dave Miller]

Dave, One reason for the staining approach is to allow me to be more productive in the darkroom. Less time spent in test prints etc.to reach satisfactory results would make my life easier. I also tend to shoot a fair amount of subjects of significant contrast so I anticipate some benefit here as well. Am I wrong in these assumptions?

You're not wrong, as I wrote earlier, I use the stuff to render the negs easier to print, and for no other reason. I like to keep the necessity for dodging and burning to a minimum.