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  1. #71
    Photo Engineer's Avatar
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    No problems with dichroic fog? That was one of Grant's fears in some baths. And, IIRC (been thinking about this), he used an organic antifoggant in some cases. Benzotriazole?

    He also used some mixed fixing agents.

    PE

  2. #72
    David A. Goldfarb's Avatar
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    I've got some fog both with and without the KBr, but it seems related to switching film batches, so it might not be or might not entirely be dichroic fog. It was a little better with KBr added, but only slightly. I'm going to try some rollfilm from yet another emulsion batch. I ran out of film from the first batch, which didn't have a fog problem. It could also be a film storage issue, since the two boxes of 4x5" had a somewhat different storage history.
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  3. #73
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    Well, Grant did use thiocyanate at very low levels in some experiments and some organic fixing agents that were never used commerically by EK. He also used a few that were used commercially.

    PE

  4. #74
    David A. Goldfarb's Avatar
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    Yes, several of the formulas in the book use organic compounds that I've never used before, and I think there's a thiocyanate formula or two in there as well, and a section on mercaptoacetic acid formulas.

    Another attraction of FX-6a that I noticed yesterday, incidentally, is that it's completely odorless.
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  5. #75
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    David;

    It just came to mind that some of Grant's favorite chemicals were the same as those used by Henn in designing Microdol and Microdol-X to prevent dichroic fog. I would have to look them up, but I think they are mentioned here and also in A&T.

    Modern films contain ingredients that tend to repress dichroic fog.

    PE

  6. #76
    David A. Goldfarb's Avatar
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    The Adox CHS100/120 looks nice and clean (105 g/l hypo, no KBr).

    I think the fog was a red herring. Looking at one particular sheet that had heavy and somewhat uneven fog, I'm now thinking it's light leaks in the area where I loaded the film.
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  7. #77
    David A. Goldfarb's Avatar
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    Here's one of the better shots from the 120 roll. Contrast is a touch on the high side, and I could give a little more exposure as a margin of safety (it could likely be that my Bronica shutter is more accurate than the leaf shutter on my 150/4.5 Xenar), but the negs look quite printable. The detail is from the full 1000 dpi scan. With these little negs, I can avoid the streaky spots on my scanner.

    The building is an Eritrean Cultural Center in the area known as "Manhattanville" west of Harlem. Columbia University is planning to buy up and tear down most of the buildings in this area to expand its campus over the next twenty years or so.

    Bronica S2a, Nikkor-O 50/2.8, f:11, 1/250 sec., handheld.
    Attached Thumbnails Attached Thumbnails EritreanCulturalCenter,29Feb2008.jpg   EritreanCulturalCenter,29Feb2008dtl.jpg  
    Last edited by David A. Goldfarb; 02-29-2008 at 07:12 PM. Click to view previous post history.
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  8. #78
    David A. Goldfarb's Avatar
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    Well, now I see what Haist means by "sludging." For my initial tests, I used the formula as a one-shot, but for the rollfilm, I mixed up a fresh batch and thought I would try re-using it. Ian was kind enough to send me a PDF of Crawley's 1961 article in the BJP, and Crawley says that it can be used for about 9-12 rolls per liter.

    The fresh formula is a pale yellow liquid, and after processing the Adox 100 it turned a transparent pink, presumably from the dyes in the film. A few hours later I noticed the whole bottle turned cloudy, and a few hours later a black precipitate was settling on the bottom. According to Haist this is caused by the developer reacting with the fixed out silver, so aside from the issue of the sludge itself, this phenomenon causes the developer to become depleted faster, reducing capacity and consistency.

    The solutions seem to involve expensive and hard to obtain organic chemicals, and since I'm not using a mechanical processor or high temperatures, the best option might be just to live with it. But say I wanted to experiment at some point, how would I get something like L-thiazolidine-4-carboxylic acid, which is used as an anti-sludging agent in a formula that has the same components as FX-6a? Can individuals order from big suppliers like Sigma-Aldrich, or is it easier to try to go through someone like Artcraft, B&S, or PhotoFormulary?
    Last edited by David A. Goldfarb; 03-01-2008 at 07:30 AM. Click to view previous post history.
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  9. #79
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    David;

    Sludging is going to be a plague in any monobath as it uses up the developing agents as well as forming sludge. Thats why they never became popular.

    Best wishes though.

    PE

  10. #80

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    Some miscellaneous others:

    Calba's Grain Maximizing Monobath
    Monobath formula for maximum grain
    Stock Solution A
    Water (45C) 700 ml
    Metol 2 g
    Sodium Sulfite (anhydrous) 50 g
    Hydroquinone 20 g
    Sodium Hydroxide 10 g
    Potassium Bromide 2 g
    Stock Solution B
    Water (25C) 300 ml
    Chrome Alum (optional) 20 g
    Sodium Thiosulfate 70 g

    Mixing instructions: Add chemicals in specified sequence. Always use cold water when
    mixing potassium or sodium hydroxide due to risk of heat reaction. In this case, reduce
    the original amount of hot water to 600 ml, and add the Sodium Hydroxide to 100ml of
    cold water prior to adding to Solution A.
    Dilution: Mix both solutions together to make 1L just before use.
    Starting point development time: 5-7 mins at 30C

    Notes: This is a monobath formula, so no fixing is required! Chrome Alum is not
    required with modern emulsions. As with any monobath formula, results can vary greatly
    depending on film type, and there is a risk of fog/staining, so you are advised to run a test
    roll before processing any important negatives.
    Ref: digitaltruth.com

    High Speed Monobath
    This was developed by the US Army Signal Corps in 1957 to process special film for
    projecting radar images.

    Water (125F) 750 ml
    Metol 12 g
    Sodium sulfite 70.9 g
    Hydroquinone 25.7 g
    Sodium hydroxide 25.7 g
    Benzotriazole 10 g
    Sodium thiosulfate 180 g
    Water to make 1 l

    The monobath was applied with a spray system. Processing time was 1.5 seconds at
    170F. Life was limited to about 2 hours due to silver precipitation.
    Ref: Dignan Photographic Newsletter, November 1974

    Keelan monobath

    Sodium sulfite 50 g
    Phenidone 10 g
    Hydroquinone 15 g
    Sodium thiosulfate (penta) 110 g
    Sodium hydroxide 18 g
    Potassium alum 10 g (disolve
    separately)
    WTM 1 l
    Process 4 to 7 minutes at 23C

    Kodak monobath film developer-fixer (1961)

    Sodium sulfite 50 g
    Phenidone 4 g
    Hydroquinone 12 g
    Sodium thiosulfate (penta) 110 g
    Sodium hydroxide 4 g

    Develop film 4 - 7 minutes at 23C (or until fully fixed)

    Monobath (Lumiere and Seyewetz)

    Sodium sulfite 30 g
    Amidol 5 g
    Trisodium phosphate 20 g
    Sodium thiosulfate 25 g
    WTM 1 l

    Process takes 15 to 20 minutes between 15 and 18C.

    Orlando monobath

    Solution A
    Metol 12.9 g
    Sodium sulfite 70.9 g
    Hydroquinone 25.7 g
    Sodium thiosulfate (penta) 180 g
    Sodium hydroxide 25.7 g
    WTM 500 ml

    Solution B
    Benzotriazole 10 g
    WTM 100 ml

    Mix solution A with solution B and add water to make 1 l.
    Process 4 to 7 minutes at 23C.
    (ref: Camera and Darkroom, May 1994)

    Five second monobath

    For rapid processing of prehardened motion picture film

    Water (90F) 750 ml
    Phenidone 2 g
    Sodium sulfite (anh) 25 g
    Chlorohydroquinone 6 g
    Glycin 6 g
    Sodium thiosulfate (anh) 10 g
    Ethanolamine 60 ml
    Water to make 1 l

    pH = 10.5
    Process film for 5 seconds at 85F to a gamma of 0.6.
    Ref: US Patent 2,901,350 (1959) to J. S. Goldhammer.
    Dignan Photographic Newsletter, November 1974

    Two second monobath

    For rapid processing of prehardened motion picture film

    Water (90F) 750 ml
    Sodium sulfite (anh) 50 g
    Sodium bisulfite 20 g
    Amidol 15 g
    Hydroquinone 5 g
    Glycin 10 g
    6-Nitrobensimidazole (0.5% soln) 80 ml (Anti-Fog)
    Sodium thiosulfate (anh) 54 g
    Ethylendiamine (85-88% soln) 60 ml
    Water to make 1 l

    pH = 10.5
    Process at 85F for 2 seconds.
    Ref: US Patent 2,901,350 (1959) to J. S. Goldhammer.
    Dignan Photographic Newsletter, November 1974

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