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  1. #1

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    Problems determining PMK/FP4 dev times for printing on variable contrast pape

    Lately I've been struggling with determining a proper N development time for FP4 using PMK Pyro. I don't have access to a densitometer, so I'm using the visual method as described by Jerry Orabona (I can't post links here yet, but if you search for "zone system development test" on google it's the first result. I've also been using a film speed test he describes, which you can find by searching for "zone system film speed test"). I've shot a few rolls now and printed test strips, and the results I'm getting are a little hard to interpret.

    For the test shots I've been shooting an evenly lit wall with no texture, out of focus, with a Hasselblad Sonnar 150mm, which was serviced recently. I'm using a Minolta spot meter and I've checked its readings against 3 35mm cameras' meters and it does seem to be accurate. I'm printing on Ilford MG RC paper, developed in Dektol 1+2, using a Beseler 65S color head diffusion enlarger at grade 2.5 (25 magenta)

    First, everyone says the proper ISO rating for this combo is 80-100. When I shoot Zone I at 100 it prints at Zone II. One stop down from the indicated Zone I reading produces a black that is just distinct from the maximum black of the a blank frame (film base + fog). This would seem to indicated that my film proper rating is 200. But this seems rather unlikely. My question is, should I reject this and test for problems with the lens or with the metering? Or is it actually possible my rating is 200?

    Second, I cannot get enough contrast out of the film. My latest test roll was developed at 70 degrees for 11 minutes and the frame showing a different shade than the paper white would be Zone 10, two stops off. This would indicate an approximate 30% increase in development time to about 14.5 minutes. Again, this seems so extreme that it makes me think I must be doing something wrong. I know that the green-yellow stain of the pyro acts as a continuously variable contrast filter on the higher values when working with variable contrast paper, so I'm wondering if that might be skewing my results? I thought maybe there would be inherent problems printing pyro negatives on variable contrast paper, but looking around at posts here and there it sounds like folks get good results with this combo. I just don't want to end up having to print everything at Grade 4 filtration to offset the stain.

    Thanks very much for any suggestions.

  2. #2
    wildbill's Avatar
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    I use that combo all the time but I'm processing in a jobo with continuous agitation. 100asa 9 minutes, sheet film and I print with a color head on vc fiber. I did all those tests when starting out and wasn't getting the results I was supposed to get so I threw all of it out and began shooting pictures, not blank walls.
    How are you agitating?
    www.vinnywalsh.com

    I know what I want but I just don't know how to go about gettin' it.-Hendrix

  3. #3
    jp498's Avatar
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    How's the enlarger doing? Is it printing normal photos well with proper contrast? Is it's lens nice and clean?

    I use tmy2 with PMK and find the combination is very sensitive to changes in agitation. Probably your combination would be as well. A developing time is useless without reference to the developing system used, agitation procedure, and timing. I haven't done any formal testing either; just zeroed in on some times and agitation styles that work for making photos with my film.

  4. #4

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    I wouldn't worry too much about the developing time being too long. I followed some of the charts suggesting dev. times for HP5 sheet film with PMK Pyro ( purchased from Bostick & Sullivan) and ended up with developing times from 18min to 22min depending on the contrast desired. Developed in an open tank. As suggested some experimentation on your part is the best way to go. I would stick with the 80-100 ISO and keep the dev. time as the only variable. I print on Ilford multigrade FB paper with an Aristo VCL4500 light source or pt/pd with my own emulsion formula. I can adjust tweaks in contrast with filtration or emulsion. For the silver prints I generally use grade 3 or 3.5 B/G on the light controls with some images calling fo split printing. I believe that HP5 will have a better stain than FP4.

    http://www.jeffreyglasser.com/

  5. #5

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    Thanks for the tips. You're all right, I did forget to mention my agitation method. I do one inversion every 15 seconds.

    I do need to try printing some non-pyro negatives to make sure there's not something amiss with the enlarger.

    The motivation for doing the tests is that I'd been shooting this combo all summer and getting what looked like decent results, judging from scans. But now that I finally got my darkroom set up in my new place and tried printing, I've found that most of the negatives have such low contrast that at grade 5 I'm only just approaching correct contrast in the print.

  6. #6
    Thomas Bertilsson's Avatar
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    Quote Originally Posted by ehtalcott View Post
    Thanks for the tips. You're all right, I did forget to mention my agitation method. I do one inversion every 15 seconds.

    I do need to try printing some non-pyro negatives to make sure there's not something amiss with the enlarger.

    The motivation for doing the tests is that I'd been shooting this combo all summer and getting what looked like decent results, judging from scans. But now that I finally got my darkroom set up in my new place and tried printing, I've found that most of the negatives have such low contrast that at grade 5 I'm only just approaching correct contrast in the print.
    If you don't get enough contrast in the print at Grade 5, then it's entirely possible you're not developing the film long enough.

    But do check the enlarger, or make a contact sheet using just white light where you expose enough so that the film rebate is paper black. That will tell you a lot about whether you need to develop longer or not.
    Make sure you use the same paper for the contact sheets that you are enlarging on.
    "Often moments come looking for us". - Robert Frank

    "Make good art!" - Neil Gaiman

    "...the heart and mind are the true lens of the camera". - Yousuf Karsh



 

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