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  1. #1
    Gregg Brekke's Avatar
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    JandC Classic 200 in PMK Pyro

    I'm looking to boost the speed of JandC Classic 200 a bit. I have been using it at 100 and developing for 14 minutes in PMK Pyro as suggested.

    Does anyone have a recommendation for shooting this film at 200 and still developing in PMK? I don't have a densitometer so thought I might start at 17 minutes to see what happens. Not sure if this is OK as the developer may have exhausted by this time. I'm also wondering if there will be an increased stain with longer development.

    The other alternative is to move to ABC or PyroCat which both bring the speed up to rated and have shorter dev times.

    Thanks,
    Gregg Brekke

  2. #2
    Eric Rose's Avatar
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    When you are talking Pyro you soon get into this Ford vs Chevy mentality, but for me at least PyroCat-HD works great. I have seen the PMK negs and was not very impressed.
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  3. #3
    Gregg Brekke's Avatar
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    This isn't about a holy war - I am looking for a suggestion from the user community...

    If I want to continue to use PMK Pyro with JandC Classic 200 rated at 200 are there any practical tips out there? Has anyone tried the following:

    Increase the concentration to 1:2:50 (instead of 1:2:100)
    Increase the temperature to 80F

    Digitaltruth lists a combination of 250 ASA with the 1:2:50 for 11 minutes.

    Just trying to tap into the vast experience of this user community.

    Thanks,
    Gregg

  4. #4

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    Quote Originally Posted by Gregg Brekke

    If I want to continue to use PMK Pyro with JandC Classic 200 rated at 200 are there any practical tips out there? Has anyone tried the following:

    Thanks,
    Gregg
    The answer is no, and in fact you won't be able to get that much effective film speed with Pyrocat-HD either.

    Effective film speed is largely a property of the emulsion for development to a given contrast range. In other words, increasing time of development from 14 to 20 minutes may result in more effective film speed, but it does so at a considerable increase in negative contrast. This will be true of all developers.

    The fact of the matter is that JandC Classic 200, and Fortepan 200 as well as Bergger BPF, which are similar if not identical films, have in fact an effective film speed of much less than 200, closer to 100 in fact, when developed to a density range of 1.05 for silver printing. In my own tests of this film, which have been conducted with sensitometry ( as opposed to the "eye-balling" procedure) I have found that the effective film speed is about 100 with PMK and D76 1:1, and about 120 with Pyrocat-HD.

    As a general rule developers that contain phenidone produce slightly more EFS than those that do not, and this explains the slight increase in film speed you get with Pyrocat-HD over the other two developers. You might get slighthly more effective film speed with a formula like FX 37 (which also contains phenidone and is about tops in the area of speed enhancing) but I very much doubt that even with this developer you can get an EFS with JandC 200 of much over 140 when developing for the negative DR of 1.05 needed for silver printing.

    Photographers who need to develop their negatives for a longer period of time to reach the high contrast needed for printing with alternative processes can rate the film for an EFS of about 200.

    Bottom line is this. If you really need an EFS film speed of 200 for silver printing you need to use another film. Changing developers or increasing time of development won't get the job done, unless you are prepared to live with negatives of much higher contrast.

    Sandy King



 

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