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  1. #11

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    Yes your "original" exposed piece of CPTN is destroyed when you develop it. You can't reuse it. The developer is a highly alkaline developing agent and the peeling apart is in essence your fixing. I remember the developer was good in the tray for a day and in the bottle for roughly a week and then your D-Max was right out the window. Crystal build up in the developer was unavoidable. If you were to develop it by hand you could try using one of those old Kodak print rollers. Soak both pieces in the activator then on a dry surface lay them together and in one stroke only roll the Kodak roller of them both to squeegee them together. Usual dwell time was 60 seconds for CPTN but since this stuff is so old 90 to 120 seconds is probably called for. Don't be disappointed if this stuff doesn't work, it didn't have a long shelf life. It was meant for a production environment and wasn't designed to sit on a shelf for long periods of time.

  2. #12
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    That's interesting. I counted last night and indeed, I have 5x 2.5L of completely unopened, full to the cap, chemistry. I wrote the ingredients down, but of course I forgot that at home.

    Glycerin, sodium sulfite, something, trisodiummonophosphate(?), something, something, propylene glycol(?), sodium thiosulfate.

    I will be getting a print roller soon actually, but I don't know if it's going to be worth using this scheme in lieu of all the other work I should be doing. I wish this chemistry was worth something to someone, but shipping liquids is impractical & like you guys have said, it's possibly kaput.
    If you are the big tree, we are the small axe

  3. #13
    holmburgers's Avatar
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    These papers... what exactly is there construction and/or mechanism for functioning?

    I'm just trying to figure out what they'd be good for; even if it's just as final supports for carbon prints or something. IDK... any ideas?
    If you are the big tree, we are the small axe

  4. #14
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    So, I did a little more reading on this Agfa Copyproof system.

    The CPTA is the receiver paper which is said to be just a sheet coated with polyethylene. The whole system works on silver-diffusion, like the instant materials I guess(?). The CPTNa negative is to be shot in-camera and then processed with the paper to make antique looking prints. I'm imagining that this is the kind of system that they used to make "old-timey" photos at amusement parks.

    Anywhoo, the receiver paper sounds to be relatively inert; so perhaps it would be good for pouring carbon tissues, or even as a temporary support in double transfer.

    None of the books I currently own cover silver-diffusion processes, but perhaps we could start a discussion about the chemistry and mechanisms involved to give me a better idea what might be possible with these materials, with "non-traditional" uses in mind.

    Thanks in advance.
    If you are the big tree, we are the small axe

  5. #15

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    Afga Copyproof process

    Quote Originally Posted by holmburgers View Post
    Last night I picked up a new camera, and with it came a couple boxes of Agfa Graphic Copyproof papers. I had no idea what these were, and still don't exactly, but it sounds like some kind of diffusion transfer process.

    I received 2 boxes of CPTA - TONE PAPER, ANTIQUE and 2 boxes of CPTNa - CONTINUOUS TONE NEGATIVE PAPER, ANTIQUE.

    Also, I have five 2.5L bottles of CP 294b chemistry.

    The CPTA says "not sensitive to light" and the CPTNa requires a red safe-light.

    What do you know about these products? What does "antique" mean? What the heck should I do with it?

    thanks!
    Afga invented this graphic arts process in the 1930s. Due to WWII it was seized as a war prices by the US and taken to Kodak for development which they failed to do for many years. Agfa did develop that market and brought it to the US. What you have are some components of that process which was originally marketed to the "Old Time Photo" trade when photographers would dress people up in costumes and take their photo with a large format camera. It is kinda like polaroid without much of the mess. But these images always came out as a sepia tone with the particular developer that you have. If you had CP296 developer it would come out a b&w tone image. Other comments that you also need a processing unit are correct. You feed the CPTN after exposure and the CPP (positive) emulsion to emulsion through a single bath unit which grabs the two and presses them together after the processing bath. Then wait a minute and peel them apart. Nearly all those photographers are now out of business or gone digital. If you had the CPN HIGH contrast negative paper then you get high contrast images as in VERY high contrast but if you used it with the CPP positive paper and the CP296 chemistry. The models of the equipment were CP38 and CP53 the number being the mm of the opening. I must have shot fifty thousand of those over the years but am retired now.

  6. #16
    AgX
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    Those materials were rather intended as copy materials in the graphic sector than as classic taking film and marketed that way.

    The processes of modern silver-salt diffusion materials had been developed both by Gevaert and Agfa in the late 30's.

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