Hybrid Double Relief Image,Double sensitized,Ammonia Softened,Dichromated Photo Paper

Discussion in 'Alternative Processes' started by Mustafa Umut Sarac, Aug 23, 2013.

  1. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    If we soften a photographic paper emulsion with ammonia
    than brush it with potassium dicromate
    and wait to dry and than
    enlarge image on to it,
    and tray develop,

    Can we get two - top relief - transparent hybrid images from one photographic paper ?

    Same applies to Film.

    Umut
     
    Last edited by a moderator: Aug 23, 2013
  2. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    I thinked little bit , If I am not wrong , dichromated gelatin requires lots of uv exposure. I dont know uv sensivity of agx. May be we can brush on to soften emulsion an red sensitive cheap daylight or an dye which is out of sensivity of below photographic paper but acts similar to below film or paper - film requires more thinking -

    May be we can pyro develop an ammonium softened paper also for relief.

    Umut
     
  3. Bob Carnie

    Bob Carnie Subscriber

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    I find that when I stand on my head things become clearer. I will try this the next time I go into the darkroom.
    I believe the yogi is on to something.
     
  4. Hexavalent

    Hexavalent Subscriber

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    Using an enlarger for pure dichromate processes is not really feasible as it requires very long (hours) of exposure, and preferably UV optics (very expensive). Fresson prints are sometime done with an enlarger, but the negative can get totally cooked during the process.

    What you are suggesting sounds like mixture of carbro and dye imbibition emulsions.

    In carbro, a bleach hardens gelatin in proportion to the amount of silver present. In a dye imbibition emulsion, a pyro type 'tanning' developer hardens the gelatin in proportion to exposed silver.

    There is another process that combines silver and a carbon-transfer type material into one, but the name escapes me at the moment.
     
  5. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    Ian,

    Thank you. As you know Ian Grant wrote that additional sensitizing is common at high tech. After his new post , I would be able to clear my mind.

    Umut
     
  6. MattKing

    MattKing Subscriber

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    You do know, Bob, that Umut is actually Dinesh, but in a parallel universe.
     
  7. AgX

    AgX Member

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    Umut, I still do not understand your idea.
     
  8. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    AgX,

    I had been posted a thread before about developing photographic paper with pyro developer and make relief.
    Answer was factory made emulsions are hardened and do not relief.
    Last night someone was talking about softening the emulsion with ammonia.

    I thought if we can soften the emulsion like homemade emulsions , we can do many things.
    I thought if we additionally sensitize the softened emulsion
    A- We can get a relief
    B- We can get two layers of photograph from single paper or film one on other.

    Ian Grant reported this commonly applied technology at high end but our emulsions are not suitable.
    Now I ask how these folks do that and which emulsion is suitable ?

    Is it makes sense ?

    Good night ,
    Umut
     
  9. Vaughn

    Vaughn Subscriber

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    I have made carbon prints with and without relief. Relief takes a much thicker layer of gelatin to remain as relief once the gelatin dries and shrinks.

    My first carbon prints had a relief when wet, but completely flattened out when dry. Seeing the wet relief is what led me to experiment and find a way to keep the relief in a dry print. I was successful, but it requires exposing a very thick layer of gelatin in the shadows and a thin layer in the highlights (by reducing the pigment concentration of the gelatin and using negatives with a high density range (2.5 or more). YMMD.