I have a Question--Direct Positive emulsion

Discussion in 'Silver Gelatin Based Emulsion Making & Coating' started by gri6o, Jul 28, 2011.

  1. gri6o

    gri6o Member

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    Hi I'm new here.
    I have a Question
    Is there a recipe for positive emulsion (something like ILFORD HARMAN) and what if it is no secret
     
  2. musila

    musila Member

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    If you don't mind crude imagery and longer exposures, check out the Calotype Society group on Flickr. There's some information on old fashioned direct positive coatings over there.
     
  3. Steve Smith

    Steve Smith Subscriber

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    I might be wrong, but I would think that if a monochrome film emulsion can be processed as a positive (which it can) then the same should be true of a paper emulsion.


    Steve.
     
  4. Photo Engineer

    Photo Engineer Subscriber

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    There are many direct positive emulsion formulas, but they are very complex and require exacting methods of precipitation.

    Although I am peripherally aware of them, I am not very familiar with them and have never made one.

    PE
     
  5. jnanian

    jnanian Advertiser

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    why not just make tintypes ?
    probably a lot less work in the end ..

    good luck !
    john
     
  6. holmburgers

    holmburgers Member

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    To quote PE from another thread...

    This is from this thread.
     
  7. Jeff Searust

    Jeff Searust Member

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    the basic theory of silver emulsion photography is reversal from the beginnings of the process in the early 1800's til today. If there were an easy way to do positives, don't you think everyone would be doing it?...
     
  8. John Shriver

    John Shriver Member

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    There are direct positive duplicating microfilms, such as Kodak 2468. I got a few 100' 35mm rolls for almost nothing, the hitch is the stuff is incredibly slow, ISO around 1 or slower...