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Thread: pyro developer, but which?

  1. #101

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    Re: pyro developer, but which?

    [QUOTE=Jay DeFehr;664745]

    Hi Jay,

    I don't agree with much in your previous post. It is your opinion but definitely not substantiated as fact. I respect your knowledge and experimentation, but I don't respect when you state opinion as fact. And frankly, much of what you state as fact is absolute nonsense, and I refer specifically to your comment that pyrogallol does not oxidize as quickly as pyrocatechol. In fact, the absolute opposite is true and you could easily verify this by using both as a sole reducer. Have you ever made that test? If not, please do so and report the results. Here is what Bill Troop (in The Film Developing Cookbook, p. 79) says about pyrocatechol. "Pyrocatechin (also called catechol, pyrocatechol, and catechin) stains and tans as well as pyro. It is generally considered to be more stable and reliable. It has been used in a few commercial developers such as Neofin Blue and even, for a brief period, in HC 110." Does Bill Troop's opinion matter? Well, I think so as he is without doubt one of the most brillant minds in the world re: photographic chemistry.

    The fact that you don't want either arbitration or consensus pretty much says it all as far as I am concerned. Sorry, but if you plan to continue to claim that 510-Pyro is the best staining and tanning developer in the world, you better plan to back it up with independent and objective testing. I have never made such a claim about my formulas, nor has Gordon Hutchings or John Wimberely. Both do great work with their formulas, as I do with mine, but as for the best formula I have never made and will never make such an absurd claim as to the best pyro developer. You should not either unless you are prepared to have your formula(s) compared with independent and objective comparison to others of its type. Even then, do you think anyone would care since by your own words developers are "interesting but not important."

    Sandy
    http://www.sandykingphotography.com/
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  2. #102

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    Re: pyro developer, but which?

    Armando,

    Testing developers against one another requires a very high degree of precision, because the differences are so small. For your results to be meaningful, you'll have to do an awful lot of testing, starting with testing for contrast, so that you can match the two developers. It's a devilishly tedious process, and few home dark rooms are equipped for it, and even fewer lab workers trained for it. How do you intend to measure contrast?

  3. #103

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    Re: pyro developer, but which?

    Quote Originally Posted by Jay DeFehr View Post
    Armando,

    Testing developers against one another requires a very high degree of precision, because the differences are so small. For your results to be meaningful, you'll have to do an awful lot of testing, starting with testing for contrast, so that you can match the two developers. It's a devilishly tedious process, and few home dark rooms are equipped for it, and even fewer lab workers trained for it. How do you intend to measure contrast?
    True, but if you use BTZS type testing, with a light integrator or sensitometer, the parameters re: contrast can be narrowed fairly quickly. From my perspective determining contrast is the least of the problems in comparing developers. The much larger issue is how to evaluate grain and sharpness since these are largely subjective issues, and depend also on many post development issues, i.e. whether you print in the wet darkroom or scan to print digitally, what type of scanner you use, how you use it, etc. etc.

    Sandy
    http://www.sandykingphotography.com/
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  4. #104

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    Re: pyro developer, but which?

    Quote Originally Posted by onnect17 View Post
    Sandy and Jay,
    I have some tmax 100 35mm I can use for testing Pyrocat-HD and 510-Pyro. Your guys are more than welcome to suggest temperature and developing time for a jobo. I can post a link to the raw images for discussion.
    You can pick the scanner: Nikon CoolScan V ED, Imacon 343 or Howtek 4000.
    Armando
    Armando,

    First, you are free to do your own testing and report the results. You don't need my permission, or that of Jay. But I will be happy to assist you with development information. I have good rotary development data for both Pyrocat-HD and 510-Pyro and would be happy to provide it to you, which would eliminate the contrast issue. My data is derived from BTZS testing and is highly portable, "if you are able to replicate exposure and development conditions."

    I would welcome independent and objective comparison. Your tests and observations will not be the end all on this issue, but they would be an interesting first step.

    Sandy
    http://www.sandykingphotography.com/
    For discussion and information about carbon transfer please visit the carbon group at Yahoo.
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  5. #105
    A.K.A Lucky Bloke ;-)
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    Re: pyro developer, but which?

    Jay,
    I understand that my test is quite limited and subjective but it will be the same for all the developers.
    First, I prepare a target. Could be a few step wedges with at least 21 bars and gray card to meter, all illuminated by a 4700K lamp. Expose one or more rolls to the same target. I use 4 or 5 exposures for each developer.
    The Jobo cpe2 is ok if I use the color thermometer, which gives 0.2C accuracy. Should be enough.
    I process the film following the recommendations for the developing time and temperature and measure density in the step wedge (help to calculate the CI).
    If possible change the time and temp to place the gray card close to density 0.75.
    Then visually compare the samples for sharpness, grain and accutance.
    Scan the negatives as positive in color. Evaluate again the same parameters per channel.
    Armando

    Quote Originally Posted by Jay DeFehr View Post
    Armando,

    Testing developers against one another requires a very high degree of precision, because the differences are so small. For your results to be meaningful, you'll have to do an awful lot of testing, starting with testing for contrast, so that you can match the two developers. It's a devilishly tedious process, and few home dark rooms are equipped for it, and even fewer lab workers trained for it. How do you intend to measure contrast?

  6. #106
    A.K.A Lucky Bloke ;-)
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    Re: pyro developer, but which?

    Sandy,
    You can save me some time with this information. What development time and temperature do you recommend to use with pyrocat-hd in rotary (one bath) as a starting point. Again, I will adjust it to get the gray card on density .75
    Thanks
    Armando

    Quote Originally Posted by sanking View Post
    Armando,

    First, you are free to do your own testing and report the results. You don't need my permission, or that of Jay. But I will be happy to assist you with development information. I have good rotary development data for both Pyrocat-HD and 510-Pyro and would be happy to provide it to you, which would eliminate the contrast issue. My data is derived from BTZS testing and is highly portable, "if you are able to replicate exposure and development conditions."

    I would welcome independent and objective comparison. Your tests and observations will not be the end all on this issue, but they would be an interesting first step.

    Sandy

  7. #107

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    Re: pyro developer, but which?

    Sandy,

    It seems you're upset. I don't appreciate your tone. I've been very respectful and don't deserve your snide comments. Your nastiness aside, it seems you don't read my posts very thoroughly. I wrote:

    Pyro works at a lower pH and is less sensitive to the stain-killing effects of preservatives, so it doesn't oxidize as quickly, and lasts longer in a tray.
    I assumed you're familiar enough with developer formulation to understand that since pyro is less sensitive to preservatives, more can be used, and the resulting developer is thereby better preserved. I have tested this, over and over, my results are consistent, and I stand by my statement.

    My statement about arbitration and consensus should be taken as my disinterest in making developer formulation a competition. I think your statement about mine says it all, about you. I don't know why you've turned so hostile. Not only do I not plan to continue claiming 510-Pyro is the best staining and tanning developer in the world, but I plan to continue having never made such a ridiculous claim. Where do you come up with this stuff? And what do you mean by, "..you better plan to back it up..."? Who do you think you are?

    Sane, rational people understand that users have different priorities in their image making, and so no one developer can possibly be best for all users. If I say, 510-Pyro is the best staining developer I've ever used (I can't remember ever having done so), what can possibly be understood by that? Only the most naive or unbalanced reader could interpret that to be meant as an unqualified absolute, even out of context. I can find pages of examples of my postings in which I describe in detail the compromises involved in developer formulation, and why, in concrete terms, there is no such thing as a best developer. Your reading is paranoiac, at best. Your insistence on grouping yourself with Troop, Wimberley, and Hutchings, opposed to me, is just pathetic, I'm sorry to say. You're taking all this WAY too personally. These are only developers, and just not very important, and no, I don't think anyone cares, except for you.

    In truth, I don't really think you care, either. It seems you just don't like to be disagreed with, no matter how respectfully. Why do you always have to ruin these discussions, when you have so much to offer?


    Other posters,

    I'm sorry for my part in the degeneration of this interesting thread. I hope everyone enjoys the holidays in good health.

  8. #108

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    Re: pyro developer, but which?

    Quote Originally Posted by onnect17 View Post
    Jay,
    I understand that my test is quite limited and subjective but it will be the same for all the developers.
    First, I prepare a target. Could be a few step wedges with at least 21 bars and gray card to meter, all illuminated by a 4700K lamp. Expose one or more rolls to the same target. I use 4 or 5 exposures for each developer.
    The Jobo cpe2 is ok if I use the color thermometer, which gives 0.2C accuracy. Should be enough.
    I process the film following the recommendations for the developing time and temperature and measure density in the step wedge (help to calculate the CI).
    If possible change the time and temp to place the gray card close to density 0.75.
    Then visually compare the samples for sharpness, grain and accutance.
    Scan the negatives as positive in color. Evaluate again the same parameters per channel.
    Armando
    Armando,

    I'm not trying to be coy, or evasive. It really is painfully demanding to generate credible data comparing developers in a home darkroom. Even if you were to generate data for grain (are you going to do an RMS granularity test, or just a subjective evaluation?), sharpness (do you have a microdensitometer, or will you evaluate subjectively?), stain (color densitometer?) and film speed (Sensitometer?), there's no way to quantify arguably the most important characteristic; gradation. My point is, no matter what numbers you come up with, someone will find a problem with your methods or your experimental design anyway, and you'll be left with a subjective evaluation. For my part, I don't care one way or the other if you test, or not, or which developer you prefer. I formulated 510-Pyro for my own use, and I've been very happy with it. If you like it too, enjoy. If you'd rather use something else, enjoy. I mean that very sincerely. I do this for fun and nothing more, and I'm not eager to get into another nasty confrontation over something as unimportant as a film developer. If I had data for TMX at hand, I'd happily share it, but I'm at work in Alaska at the moment, and don't have access to that data. Best of luck, and happy holidays.

  9. #109

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    Re: pyro developer, but which?

    Jay,

    Instead of blaming me for the degeneration of this thread you might consider the nature of your own participation on this forum. You were absent from LF forum for two or three years and during that time I don't recall even one thread on pyro that was confrontational.

    Yes, I am irritated with this exchange, not because I don't like to be disagreed with but because I don't like it when people state opinions as fact, and when they use selective information to prove a point, and when they argue points incessantly. But why should I bother to discuss anything with you because you always insist on having the last word? So I will just concede that pyrogallol is a soft working developer and that pyrogallol is much superior to pyrocatechol and be done with any more discussion with you.

    Have a Happy Holiday, Jay

    Sandy
    Last edited by sanking; 25-Dec-2010 at 10:58.
    http://www.sandykingphotography.com/
    For discussion and information about carbon transfer please visit the carbon group at Yahoo.
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  10. #110

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    Re: pyro developer, but which?

    Quote Originally Posted by onnect17 View Post
    Sandy,
    You can save me some time with this information. What development time and temperature do you recommend to use with pyrocat-hd in rotary (one bath) as a starting point. Again, I will adjust it to get the gray card on density .75
    Thanks
    Armando
    Armando,

    For what film (s) would you like the data?

    Sandy
    http://www.sandykingphotography.com/
    For discussion and information about carbon transfer please visit the carbon group at Yahoo.
    https://groups.yahoo.com/neo/groups/...nTransfer/info

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