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  1. #1
    aaronmichael's Avatar
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    Paper Negative Reversal Process

    Not sure if this is supposed to be posted in this forum but I figured a lot of pinhole photographers work with paper negatives and that's what my question is about. I want to try the reversal process with some of my 8x10 pinhole paper negatives (that I'll shoot in the future). I've read some things about how it's done but am still a little confused. Also, in my case, I'd be doing this at the lab at school so - could someone give me a quick explanation of how it's done and tell me what I need to ask the people working at the lab for when I try it out. This is just for fun so I don't need to use the best of whatever chemicals, I'd be happy with any results even if they were bad. We very well might not even have the right things at the lab to do it. Any instruction would be greatly appreciated!

  2. #2
    Photo Engineer's Avatar
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    You will need Dektol, Sodium Hypo, Potassium Dichromate, Sulfuric Acid, Hardening fixer, and Sodium Sulfite.

    Process:

    Dektol 1:2 or 1:3 for 1 - 3 minutes DBI..
    clear in Sodium Sulfite bath (about 20 g/L) 1 min
    Wash 1 - 2 mins.
    Bleach in Dichromate + Sulfuric acid (formulas all over APUG and elsewhere for this)
    clear in above clear about 1 min
    Wash 5 mins
    Turn on the lights and FOG the paper front and back.
    Dektol again but with 500 mg /l of Sodium Hypo, DBI again.
    Stop
    Hardening fix
    Wash

    This should work. There are many many alternates for the bleach and the redeveloper.

    PE

  3. #3
    aaronmichael's Avatar
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    Quote Originally Posted by Photo Engineer View Post
    You will need Dektol, Sodium Hypo, Potassium Dichromate, Sulfuric Acid, Hardening fixer, and Sodium Sulfite.

    Process:

    Dektol 1:2 or 1:3 for 1 - 3 minutes DBI..
    clear in Sodium Sulfite bath (about 20 g/L) 1 min
    Wash 1 - 2 mins.
    Bleach in Dichromate + Sulfuric acid (formulas all over APUG and elsewhere for this)
    clear in above clear about 1 min
    Wash 5 mins
    Turn on the lights and FOG the paper front and back.
    Dektol again but with 500 mg /l of Sodium Hypo, DBI again.
    Stop
    Hardening fix
    Wash

    This should work. There are many many alternates for the bleach and the redeveloper.

    PE
    Thanks for the quick reply and step by step instructions. Can any of the chemicals be eliminated or are all of them required and if all of them are required do they have names besides their chemical names? I just want the greatest chance of our lab having what I need. Since it's in a class darkroom, not my personal one, can I fog the paper under the enlarger rather than turning the lights on? Wouldn't want to kick everyone out of the darkroom just to fog my paper.

  4. #4
    Photo Engineer's Avatar
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    Your best bet is to use a prepared reversal kit.

    An enlarger might be too weak in output to fog the paper correctly.

    Take the paper out of the darkroom and fog it in room light.

    There are dozens of methods for doing this type of process.

    PE

  5. #5
    aaronmichael's Avatar
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    Quote Originally Posted by Photo Engineer View Post
    Your best bet is to use a prepared reversal kit.

    An enlarger might be too weak in output to fog the paper correctly.

    Take the paper out of the darkroom and fog it in room light.

    There are dozens of methods for doing this type of process.

    PE
    Thanks, appreciated.

    Anyone else care to chime in?

  6. #6

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    Hi,

    FYI, you don't have to do this with your in-camera paper. You can just make a negative and use a contact printing frame to smash it face to face with another piece of paper. It is just like making a contact print or proofsheet. And you get more control of contrast that way, and can burn/dodge.

    Especially since you are in a group lab, this would probably be a preferable way to go about it. At least until you set up your own darkroom...and for the reversal procedure, it literally just needs to be "A Dark Room," with some trays in it. No enlarger necessary.
    2F/2F

    "Truth and love are my law and worship. Form and conscience are my manifestation and guide. Nature and peace are my shelter and companions. Order is my attitude. Beauty and perfection are my attack."

    - Rob Tyner (1944 - 1991)

  7. #7
    aaronmichael's Avatar
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    Quote Originally Posted by 2F/2F View Post
    Hi,

    FYI, you don't have to do this with your in-camera paper. You can just make a negative and use a contact printing frame to smash it face to face with another piece of paper. It is just like making a contact print or proofsheet. And you get more control of contrast that way, and can burn/dodge.

    Especially since you are in a group lab, this would probably be a preferable way to go about it. At least until you set up your own darkroom...and for the reversal procedure, it literally just needs to be "A Dark Room," with some trays in it. No enlarger necessary.
    Well the problem is that I've made many contact prints with paper negatives and I'm just starting to get bored with it which is why I wanted to try out the reversal process for fun. Maybe I'll just have to get creative with my contact printing to keep me entertained until I personally have the proper chemicals and setting to do it.

  8. #8
    tomalophicon's Avatar
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    There is a positive paper available from Ilford. You probably knew that already.

  9. #9
    aaronmichael's Avatar
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    Quote Originally Posted by tomalophicon View Post
    There is a positive paper available from Ilford. You probably knew that already.
    If it came in a sample pack or something then I'd go for it. I just don't feel like paying over $2 a sheet for 8x10.

  10. #10
    aaronmichael's Avatar
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    Some question about process and chemistry:

    1. Does the sodium hypo = sodium hypochlorite?
    2. Where can I find the potassium dichromate if we don't have it at the lab? Would Freestyle carry it?
    3. Where can the sulfuric acid be found if we don't have it at the lab?
    4. How long should the paper be fogged for under indoor lights before it's taken back into the darkroom?

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