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  1. #11

    Join Date
    Oct 2004
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    Westport, MA.
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    I've had decent success with doubling the A solution and cutting development time by 20 to 30%. *shrug*

    For a while I was using Acufine and Microphen on 4x5 film in a Uniroller and no matter what, I would get streaks. Prewet/prewash, Photo-flo/jet dry in every combination. Nothing.

  2. #12

    Join Date
    Jan 2005
    Location
    Downers Grove Illinois
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    1,052
    Rotten luck, the developer oxididizes. Hutching recommends a nitrogen blanket in his book.

    4x5 in PMK is best dome in a sealed developing tank using inversion with little air. 4x5 nikor or jobo 2500 with the 6 sheet reel. With the Jobo, fill the bottom with developer, add the reel then more solution but not completely to the top as you need room for liquid movement. The developer comes out the same color as you started with, not so with open trays or tanks. The time will be much shorter too, as the developer will not spoil slowing the process.

    I now do 35 mm PMK in in closed tanks also it worked so well.

    Agitate i inversion and twist every 15 sec.

    Write up how you do.

  3. #13

    Join Date
    Jun 2005
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    Seattle
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    Large Format Pan
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    Photo Formulary and ABC Pyro

    Photographer's Formulary worked with Harald Leban's formulas for Roto Pyro and came up with their spin on it (so to speak). Theirs is ABC Plus. Bob and team took the time to do extensive testing with various films and provide the results with their datasheet.

    http://www.photoformulary.com/Deskto...ion=0&langId=0

    One of the problems of any Pyro in rotary processors is foaming. I use a silicon anti foaming agent in extremely small quantity -- like 1 ml per liter -- to kill the foam. Being the LF on a shoe string type I am, I use the super fancy Rug Doctor Anti-Foam solution available at super markets and home improvement stores everywhere.

    http://www.rugdoctor.com/cleaning_products.aspx

  4. #14

    Join Date
    Mar 2003
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    Greenville, SC
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    Quote Originally Posted by Dr. Dagor
    Photographer's Formulary worked with Harald Leban's formulas for Roto Pyro and came up with their spin on it (so to speak). Theirs is ABC Plus. Bob and team took the time to do extensive testing with various films and provide the results with their datasheet.

    http://www.photoformulary.com/Deskto...ion=0&langId=0

    http://www.rugdoctor.com/cleaning_products.aspx
    The names are a little confusing, but just for the record the developer sold by Photographers' Formulary as ABC Pyro Plus is for all practical purposes the same as Rollo Pyro sold by Bostick and Sullivan. One of the interesting features of Leban's ABC Pyro Plus/Rollo Pyro formula is that it is one of the first pyrogallal based developers to use ascorbic acid.

    Harald Leban originally called his formula ABC+ but it was marketed by Bostick and Sullivan as Rollo Pyro.

    Of course, don't confuse the Formulary ABC Pyro Plus with the original ABC Pyro because they give very different results.

    Just for the record, I modified the ABC Pyro Plus/Rollo Pyro formula by substituting phenidoine for metol in the original formula and making it a one solution developer (you just mix with water to get a working solution) and I call this Rollo TEA. Its working characteristics are very similar to the original Rollo Pyro, though it is a bit more active.

    The formula for Rollo Tea is as follows.

    For 100 ml of stock solution, mix in the order as noted below. For a liter of stock solution multiply the amounts by 10X.

    Rollo-TEA

    TEA at 175º F
    Potassium bromide — 0.2 g
    Sodium bisulfite — 2.0 g
    Pyrogallol — 15.0 g
    Ascorbic acid — 1.0 g
    Phenidone — 0.2 g

    Add TEA to 100 ml

    For use, dilute 1:100 for silver printing or 2:100 for alternative work. The substitution of phenidone in place of metol at a ratio of one part phenidone for ten parts metol gives a lot of additional synergism to the developer and shortens development times.

    The advantage of the Rollo-TEA formula over the original Rollo Pyro formula, are:

    1. Rollo-TEA is a single solution developer to which one need add only water to have a working solution.

    2. With the substitution of phenidone for metol there is an increase in synergism. This gives shorter development times.

    Like Rollo Pyro, Rollo TEA is very clean working, with very tight grain and gives low B+F values in rotary processing, as in Jobo, BTZS type tubes, etc.

    The color of the stain is typical of pyrogallol based developers, ranging from greenish to greenish/yellow, or yellow/brown.

    Given their origin, composition and characteristics it is not unreasonable to call both ABC Pyro Plus/Rollo Pyro and Rollo TEA as direct descendants of PMK, kind of like PMK on steroids.

    Sandy

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