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  1. #11

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    Quote Originally Posted by Jorge
    Sandy, I tried the semi stand development and your curves confirm my first impression. It seems that for extended development and even for the "normal" development the b+f is quite high. Has this been a problem with your pt/pd printing and lenght of exposures?
    Yes, there is quite a bit more general stain created with this type of development and it does increase printing time significantly with UV processes. But the curious thing is that the used developer is perfectly clear, even after as much as 1.5 hours of development. Normally we figure that the creaton of general stain with pyro developers results from oxidation which causes it to turn browner and browner with time. But in this case the reason for the increase in general stain would appear to be something other than oxidation.

    Sandy

  2. #12
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    Quote Originally Posted by sanking View Post
    Yes, there is quite a bit more general stain created with this type of development and it does increase printing time significantly with UV processes. But the curious thing is that the used developer is perfectly clear, even after as much as 1.5 hours of development. Normally we figure that the creaton of general stain with pyro developers results from oxidation which causes it to turn browner and browner with time. But in this case the reason for the increase in general stain would appear to be something other than oxidation.

    Sandy
    I've read somewhere in APUG that the increase part A would lower BF (1.5:1:150), isn't it?
    I've plan to test the TMY 8x10 for Pt/Pd print with Pyrocat HD semi-stand with BTZS tube. Which dilution and set of time should I use to run on winplotter.

    Thanks,
    TN

  3. #13

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    Quote Originally Posted by TN98 View Post
    I've read somewhere in APUG that the increase part A would lower BF (1.5:1:150), isn't it?
    I've plan to test the TMY 8x10 for Pt/Pd print with Pyrocat HD semi-stand with BTZS tube. Which dilution and set of time should I use to run on winplotter.

    Thanks,
    TN
    I use a 1.5:1:200 dilution for TMY and extreme minimal agitation (four agitation periods).

    Try about 30-40 minutes with this dilution at 70F if you plan to print on VC silver papers. Agitate very vigorously at the beginning for about 1.5 minutes, then gently for 15 seconds for the other agitation periods.

    Sandy King

  4. #14
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    What is the time for Alternative Process like Pt/Pd?

  5. #15

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    That's a lot of non-image density; whether it's fog or general stain, but it shouldn't be a major problem for rollfilm shooters developing for density ranges around 1.0 to print on middle grades of paper. I don't think Sandy's or Tom's developing data is intended for silver papers, and I don't know how they tolerate so much non-image density for Alt processes.

  6. #16

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    Quote Originally Posted by cahayapemburu View Post
    That's a lot of non-image density; whether it's fog or general stain, but it shouldn't be a major problem for rollfilm shooters developing for density ranges around 1.0 to print on middle grades of paper. I don't think Sandy's or Tom's developing data is intended for silver papers, and I don't know how they tolerate so much non-image density for Alt processes.


    Where did you get the data for B+F? My own B+F for the times specified was .17 at 30 minutes to .25 for 40 minutes. And the absolute B+F of the film, with development of five minutes in a non-staining developer, was .12, so we only added log .05 with 30 minutes of development, which seems very low to me.

    The developing data I gave was indeed intended for silver printing, specifically on VC papers with diffusion type light source. For that type of printing my opinion is that you need a negative with a CI of about .55-.65, which gives a DR of about 1.35 with a staining developer. With TMY I get this CI with Pyrocat-HD and the 1.5:1:200 dilution with between 30-40 minutes of development, with the agitation type specified, i.e. Extreme Minimal.

    The above assumes analysis by blue mode densitometry.

    Sandy King

  7. #17

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    Quote Originally Posted by TN98 View Post
    What is the time for Alternative Process like Pt/Pd?
    Turns out that you need about the same time for pt/pd. A DR of about 1.35 by blue mode turns out to be a DR of about 1.85 by UV mode, and that works fine for printing with many alternative processes, including pt/pd. You would need a bit more for printing with albumen, salted paper, pure palladium or VDB, up to log 2.5.

    Sandy King

  8. #18

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    Quote Originally Posted by cahayapemburu View Post
    That's a lot of non-image density; whether it's fog or general stain, but it shouldn't be a major problem for rollfilm shooters developing for density ranges around 1.0 to print on middle grades of paper. I don't think Sandy's or Tom's developing data is intended for silver papers, and I don't know how they tolerate so much non-image density for Alt processes.
    cahayapemburu, You wrote: That's a lot of non-image density; whether it's fog or general stain.

    What data did you base that statement on? It is not consistent with the D log E curves I posted.
    Tom Hoskinson
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  9. #19

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    Quote Originally Posted by Tom Hoskinson View Post
    cahayapemburu, You wrote: That's a lot of non-image density; whether it's fog or general stain.

    What data did you base that statement on? It is not consistent with the D log E curves I posted.
    Tom,

    In reading back through the thread I think cahayapemburu must have gotten those values from the data in a family of curves I posted several years ago, in July 2004 to be exact. I was confused because I thought he was referencing one of the new messages.

    The B+F values are pretty high because, 1) the tests were made with TMY film that was fairly old, with a fair amount of B+F from aging, and 2) the readings were based on UV analysis, not Blue as I indicated in the messages that accompanied the image file.

    And yes, as Jorge indicated back then, and I recognized, B+F times get very high with UV mode when you develop with a staining developer for very high CI. And especially with aged fillms. The times get very long even with non-staining developers and fresh film.

    Sandy
    Last edited by sanking; 03-08-2008 at 04:24 PM. Click to view previous post history.

  10. #20

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    I was commenting on the data posted in this thread; maybe it's the old data based on outdated film? I won't ask why one would publish that kind of data; I'm sure Sandy has his reasons, but what I do wonder is why Sandy feels VC papers require such high density ranges? Scaling negatives for a paper grade between 2 and 3 is widely recommended and commonly practiced for maximum flexibility in printing, and a thin negative consistent with optimum sharpness and minimum grain. These negatives should have a density range around 1.0. Keeping in mind these values are logarithmic, 1.65 is much, much more dense than 1.0; what is gained by so much added density?

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