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  1. #1
    noseoil's Avatar
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    PMK to Pyrocat HD or PCTEA?

    With 2 years of darkroom experience behind me now, I'm wanting to try another film developer. I've been using PMK and have been pleased with results, but... There is the issue of cloudiness in shadow detail which I'm not pleased with, especially in contact printing.

    I've used ABC pyro, but have found it too fickle and energetic for casual use with the slow films I prefer (25 and 100). It does yield fine negatives with razor sharpness, but is more labor, cost and chemistry intensive than PMK.

    My concerns are these. I want a long shelf life, as I can go for weeks at times without developing at times and don't want to have to mix fresh stock (B in ABC, for example). Shadow values need to be crisp, not muddy (PMK's major drawback). Highlight values seem to be best with pyro, so I would like to stay with a developer which can mask with a proportional stain affecting these values.

    I'm not really too concerned with speed, as shooting at asa 12 (PMK) and asa 3 (ABC) with 25 speed film is not a problem now, although there are limits to DOF and shutter speeds. Both Pyrocat and PC TEA seem to be easy to use one shot developers which are very cost effective. Any ideas? thanks, tim

  2. #2

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    Tim,

    I have not used the TEA formulations so I really can not comment in that regard. I have found Pyrocat to be preferable to PMK because of the issue of the color of stain if for no other.

    I am not alone in realizing this issue. Howard Bond in his recent studies in PhotoTechniques addressed this issue as well. The PMK stain color, while proportional, will act as a contrast reduction factor on VC materials in the highlight regions. Of course if one is using graded materials this will not apply.

    I have found that the sharpness and tonal scale with Efke PL 100 4X5 (minimal agitation) will rival a contact print in enlargements up to and including 11X14.

    The issue of poor shadow tonal separation that you raise could be partly due to the film that one is using. If a given film chararacteristic curve has a long toe and the exposure is placed on the toe then the result will be poorly differentiated shadow tonal scale. Taking TriX developed in HC 110, for instance, I have found that the EI for that film (based on densitometric evalutation) is 160 but in actuality when I place my shadow exposure on Zone IV then I am actually adjusting the EI to 20. That is what many photographers do because of the characteristics of the film curve. There is really no other way to evaluate a film properly other then to evaluate or even to plot the curve if it is not readily available. I aplologize for my digression but felt that this needed to be addressed for evaluation of the matters that you raised.

  3. #3
    noseoil's Avatar
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    Donald, thank you for your input. I'm aware of the film toe's threshold and yes, I have underexposed a time or two. After comparing ABC and PMK with respect to shadow values, the ABC is much better in a scene by scene comparison. My concern with shadow placement on zone IV is the subsequent lifting of zone VIII into the shoulder and a loss of detail in highlights. This is certainly more critical with Efke 25 than it is with Efke 100.

  4. #4
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    PC-TEA is, of course, a non-staining developer in a concentrated stock solution containing only phenidone, ascorbic or erythorbic acid and triethanolamine that requires nothing but water to activate it. The stock solution alone will not develop film. It lasts a very long time on the shelf. One can substitute pyrogallol or catechol for the ascorbic acid to obtain a staining developer concentrate with the same keeping qualities and the same need for water only in order to make active developers.

    I have found that when one uses PMK or one of my staining developers with VC paper, the shadows are there but need a little local contrast to bring them up. I use about 30M filtration or an Ilford #3 filter. The same negative prints very well on #2 graded paper because the colored part of the image is seen as extra silver by the blue sensitive paper. As has been pointed out by others before me, the pyro image is usable also with those alternative processes that require a very high contrast negative.
    Gadget Gainer

  5. #5
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    Tim-

    I can tell you that Efke 100 in Pyrocat-HD is my favorite combination by far. I'm only doing contact printing (on Azo and on both graded and VC fiber papers), and the results have been gorgeous. I get excellent separation of shadow detail and negatives that I can use for either type of paper easily, all from a developer that's inexpensive and seems to keep forever.

    I have not tried PC-TEA yet, although I will be doing so in the new year. Unfortunately, I have not developed any Efke 25 with Pyrocat-HD, as my current personal project is limited to Efke 100 only. I'll be interested to hear what others have to say about Pyrocat-HD and Efke 25.

    Be well.
    Dave
    Film is cheap. Opportunities are priceless.

  6. #6

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    Quote Originally Posted by noseoil
    Donald, thank you for your input. I'm aware of the film toe's threshold and yes, I have underexposed a time or two. After comparing ABC and PMK with respect to shadow values, the ABC is much better in a scene by scene comparison. My concern with shadow placement on zone IV is the subsequent lifting of zone VIII into the shoulder and a loss of detail in highlights. This is certainly more critical with Efke 25 than it is with Efke 100.
    Tim,

    Thanks for your thoughts. I would like to comment on your concerns about the Zone VIII "fall" in the example that you have provided.

    The Zone VIII density would be a condition of exposure, certainly. But it would also involve the film and the development times.

    As I review the characteristic curve for Efke 25 as found on the JandC site, I find that this film exhibits a perfectly linear straight line once one departs from a slight toe (except in cases of greatly extended development). I would not consider the film's shoulder when I exposed this film.

    Other films may incorporate this consideration but Efke 25 does not appear to be among those.

  7. #7
    noseoil's Avatar
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    Donald, my concern was that putting the shadow values on zone IV instead of III would compress the top end of the film's range and crowd the top end. You are saying that a shift of one stop up the curve will not affect the highlights, but just move everything up a notch and add density to the negative, requiring more time in printing.

    Development time can remain the same without causing problems? I'm seeking a clarification of your statement, as I was concerned that by adding a stop of exposure I would have to reduce development times to keep things the same. Perhaps my understanding, specifically with respect to Efke 25, has been wrong all along. Thanks.

  8. #8

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    Quote Originally Posted by noseoil
    Donald, my concern was that putting the shadow values on zone IV instead of III would compress the top end of the film's range and crowd the top end. You are saying that a shift of one stop up the curve will not affect the highlights, but just move everything up a notch and add density to the negative, requiring more time in printing.

    Development time can remain the same without causing problems? I'm seeking a clarification of your statement, as I was concerned that by adding a stop of exposure I would have to reduce development times to keep things the same. Perhaps my understanding, specifically with respect to Efke 25, has been wrong all along. Thanks.

    Tim,
    According to the characteristic curve that JandC has posted in the Efke technical section on their site, Efke 25 will develop all sorts of density range well beyond what we require for any photographic process today. Recognizing of course that the developer that they are using is not Pyrocat, the density range for a four minute developing time has no shoulder and a density range above 2.00 with no shoulder shown. At seven minutes the density range is above 2.60 with the most subtle shoulder. At 10 minutes the density range is above 3.00 and a subtle shoulder albeit slightly more then the seven minute development time.

    Recognizing that I want a density range of 1.55-1.65 for grade two Azo and Pt-Pd would be 1.65-1.75 you can see that this film has a great deal of expansion potential.

    I have not used this film myself but I would think that this film could be exposed at EI 25 placing the shadows at Zone IV (Actual EI of 3) and this film would work wonderfully at N and N+ development.

    If one were to need two or three zones of expansion this film could be exposed at EI 6 or 12 with wonderful expansion capabilities. In fact if one could deal with the slow emulsion this is one of the better films for expansion today based on the material provided on the JandC site.

    I would think that a good choice of two films would be Efke 25 for expansion and HP 5 for contraction. That is if the slow film speed with the Efke 25 would not be problematic in your application.

    I hope that this answers your question.

  9. #9
    noseoil's Avatar
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    Don, thank you for your explanation. It makes sense. tim

  10. #10
    roteague's Avatar
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    View Camera magazine had an article a few months ago (May/June??) about PMK and Pyrocat HD. Worth reading.
    Robert M. Teague
    www.visionlandscapes.com
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    "A man who works with his hands is a laborer; a man who works with his hands and his brain is a craftsman; a man who works with his hands and his brain and his heart is an artist" -- Louis Nizer

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