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  1. #1

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    Hydrogen peroxide "steaming" to gain add'l speed.

    I was going over Anchell/Troop to read up on speed increasing additives and I came across a piece on using h202 to "steam" film to get a speed increase. I've never done this (surprised I haven't, actually) and am looking to try it out.

    Has anyone experience with doing this? Output from negatives "steamed" in this way?

    Thanks!

  2. #2

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    Back in the days before digital, astronomers used a variety of techniques to hyper sensitize plates. I believe H2O2 was one such technique.

  3. #3

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    Some hypersensatizing methods are discussed here.

    http://en.wikipedia.org/wiki/Photogr...rsensitization

  4. #4
    AgX
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    In any case either the liquid or its vapour were employed. No boiling of H2O2 was involved.

  5. #5
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    Hypersensitization doesn't increase speed. It decreases reciprocity failure.

    It also works best with slow films, like Tech Pan. Hypered Tech Pan is one of the fastest films when it comes to 6 hour exposures. For TP and astro films (TP was originally 'solar flare patrol film' - hence the extended red sensitivity for imaging the hydrogen line, making it beloved of amateur astronomers) there is some modest across the board speed increase, but nothing to write home about - I ordered some hydrogen hypered TP once, maybe it was ASA 40 rather than 25 for normal use.

    Hypersensitization won't do anything for you if you are trying to get more speed out of Tri-X.
    Last edited by Nicholas Lindan; 02-18-2013 at 12:38 PM. Click to view previous post history.
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  6. #6
    Rudeofus's Avatar
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    And that seems to be the main problem with these "I gain two stops if I immerse the film in toad liver for two days around full moon" recipes: they won't improve the speed of modern and fast films, where we would like it most.
    Trying to be the best of whatever I am, even if what I am is no good.

  7. #7
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    Quote Originally Posted by fotoobscura View Post
    I was going over Anchell/Troop to read up on speed increasing additives and I came across a piece on using h202 to "steam" film to get a speed increase. I've never done this (surprised I haven't, actually) and am looking to try it out.

    Has anyone experience with doing this? Output from negatives "steamed" in this way?

    Thanks!
    To quote my stock phrase, why would you wish to do this?

    “The contemplation of things as they are, without error or confusion, without substitution or imposture, is in itself a nobler thing than a whole harvest of invention”

    Francis Bacon

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    Set aside the sarcastic "question with a question" responses, thanks for the information folks!

    Yes Anchell suggests that you should not try this with t-grain films which makes sense considering their improved latitude out of the box.

    Nicholas- interesting and informative reply, thanks. Anchell doesn't suggest this is to be used to offset reciprocity failure, he indicates that film pushed 2-3 steps will benefit from greater shadow detail using this method. Most importantly, and why I am thinking about trying this at all is the part where he indicates 'the results are grainy but have a unique quality that often complements low light photography aesthetics." This is very interesting to me as a lot of my subjects are in this environment but not limited to long exposures at night with slow "traditional" films (e.g. efke/adox).

    Thanks!

  9. #9
    Athiril's Avatar
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    H2O2 and Mercury hypering improved Provia 400X pushed to 1600 results for one user.


    Researching semiconductor technology may provide better educated guess starting points for things to try.


    Quote Originally Posted by Rudeofus View Post
    And that seems to be the main problem with these "I gain two stops if I immerse the film in toad liver for two days around full moon" recipes: they won't improve the speed of modern and fast films, where we would like it most.
    What methods have you tried with which modern films and found no effect?
    Last edited by Athiril; 02-18-2013 at 04:02 PM. Click to view previous post history.

  10. #10

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    The Anchell books contain quite a few errors so read them cum grano salus.

    You use a SS two reel tank with a small amount of 3% hydrogen peroxide in the bottom. An empty reel actrs as a spacer between the film and the peroxide. The film is left for a number of minutes which must be determined by trial and error for each film used. The film must be used shortly after treatment and cannot be stored as it reverts to its normal unsensitized state quickly.
    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

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