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  1. #1
    cinejerk's Avatar
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    More questions about B&W reversal processing

    I've been playing around with black and white reversal processing. Right now I'm trying some old 16mm movie film and I'm seeing really thin dmax.

    Here is the run down on the chemistry. For first developer I'm using D-19 with 2g sodium thiocyanate. Bleach is chromate sulfuric. Then a sulfite clearing bath. Second developer right now is dektol. Then fixer.

    I guess my main question is what influences dmax the most in this type of process?

    There are a lot of variables here so I can't expect to pin it down exactly but some ideas might help.

    Using this exact same chemistry I have had much better results with a different film.
    Possibly my chemistry is getting weak, I don't know.

  2. #2

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    Quote Originally Posted by cinejerk View Post
    Right now I'm trying some old 16mm movie film and I'm seeing really thin dmax.
    Old film which would produce a lot of fog when processed as a negative will produce a thin positive. Remember everything is backwards when doing reversal processing.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  3. #3
    cinejerk's Avatar
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    Hi Gerald and John

    I think you guys hit the problem on the head. I processed a clip of the film with just first developer and then to the fixer.
    Came out really foggy.

    John I am using thiocyanate in the first developer. In a way I guess that is acting like hypo.

    Do you think there might be some kind of compromise that I can try to improve this a little?

    Maybe a little less exposure and a little less time in the first developer?

    What would anti-fog do? Probably do the same as less first dev time.

  4. #4

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    If your film came out really foggy as you say then there is no way to really salvage it. If you add enough antifog to eliminate a serious fog problem the film speed is also reduced. There does come a time when old film needs to be discarded.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  5. #5

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    Your film is fogged, Kodak has 16mm tri-x at a good price on their web site. I had about 1000 feet of old film and it was badly fogged, useless except for testing fixer clearing time. I have been taking movies with the tri-x, but it is easy to over expose, which gives a very thin positive. I'm using the H-7 process with a Morse rewind tank. Have fun experimenting.

  6. #6
    cinejerk's Avatar
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    Hi Chris
    Yep it's probably time to buy some film.
    I tried to reduce the first developer time and the positives just started getting really foggy.
    My initial point is probably as good as it will get.
    The images are there it's just the blacks are not as black as they should be.

  7. #7
    cinejerk's Avatar
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    Hi John
    Yes that's exactly what I have, the minolta 16. I reload those tiny plastic cassettes.

    But I find that I can just buzz off a foot or so of film in my bolex. Then cut off that piece in a dark bag and
    load it into my yankee clipper roll tank.

    I actually find that faster then messing with the little minolta.

  8. #8

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    I made a post in my bloggy blog a while back about how I reversal process black and white film. Not saying this is the best way, but it works for FP4+ very well, I think. My projector died on my (a used JC Penny model. Didnt expect much life out of it :/), so I havent done it in a while

    http://silver-light0.blogspot.com/20...and-white.html
    "Gotta little problem with personal space, and I've been pounding the Jager. My breath and behavior have been driving the patrons away" -"Whipped Cream" by Ludo


    My photography blog: http://silver-light0.blogspot.com/

  9. #9

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    The same but different

    I have had great success reversing plus x pan, but something you said threw me. I experimented with different exposure indexes, and had the best results shooting plus x at 500 ASA! Anything less resulted in progressively thinner positives. As for chemicals, I think I got the recipe from the darkroom cookbook. The first developer is D-76 1:1 with a smidge of sodium thiosulfate. The bleach is potassium dichromate and sulfuric acid, and the second developer is Dektol. I am at a loss to understand how 32 ASA will work. I wish I had a scanner so I could show how good these look. Unfortunately I will have to start again now that plus x is gone.

    Best regards,
    Chris

  10. #10

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    Quote Originally Posted by Chris Douglas View Post
    I have had great success reversing plus x pan, but something you said threw me. I experimented with different exposure indexes, and had the best results shooting plus x at 500 ASA! Anything less resulted in progressively thinner positives. As for chemicals, I think I got the recipe from the darkroom cookbook. The first developer is D-76 1:1 with a smidge of sodium thiosulfate. The bleach is potassium dichromate and sulfuric acid, and the second developer is Dektol. I am at a loss to understand how 32 ASA will work. I wish I had a scanner so I could show how good these look. Unfortunately I will have to start again now that plus x is gone.

    Best regards,
    Chris

    dunno what to tell you about the differences in exposure indexes we got . I wonder if the sodium thiosulfate and our different choices in first developer has anything to do with it?

    If I could scan mine, I'd post them. my projections look great, imho. Maybe if I ever get another projector or fix mine, I'll post photos of the projections. But then, I'd have to use the kind of camera that brings forth much buttrage among the users of these forums
    "Gotta little problem with personal space, and I've been pounding the Jager. My breath and behavior have been driving the patrons away" -"Whipped Cream" by Ludo


    My photography blog: http://silver-light0.blogspot.com/

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