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Thread: ASA developer

  1. #11
    TheToadMen's Avatar
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    Quote Originally Posted by Trask View Post
    I'd like to see some formulas if anyone wishes to post
    Did you see this thread?
    http://www.apug.org/forums/forum37/1...here-when.html
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  2. #12

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    Acufine Substitute

    Suggested by Paul Farber in Photographic (Oct 1984).

    Distilled water (50°C) …………………………………………… 750 ml
    Phenidone ……………………………………………………………………………… 0.28 g
    Sodium sulfite (anhy) ……………………………………………… 60.0 g
    Hydroquinone ……………………………………………………………………… 5.0 g
    Sodium carbonate …………………………………………………………… 2.5 g
    Borax ………………………………………………………………………………………… 2.75 g
    Potassium bromide ………………………………………………………… 0.9 g
    Distilled water to make ………………………………………… 1.0 l

    Ilford Autophen

    Distilled water (50°C) …………………………………………… 750 ml
    Sodium sulfite (anhy) ……………………………………………… 100 g
    Hydroquinone ……………………………………………………………………… 5.0 g
    Borax (deca) ……………………………………………………………………… 3.0 g
    Boric acid …………………………………………………………………………… 3.5 g
    Phenidone ……………………………………………………………………………… 0.2 g
    Potassium bromide ………………………………………………………… 1.0 g
    Distilled water to make ………………………………………… 1.0 l
    Last edited by Gerald C Koch; 10-03-2013 at 02:36 PM. Click to view previous post history. Reason: Corrected per Ian's later post to Autophen rather than Microphen.
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  3. #13
    Ian Grant's Avatar
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    Quote Originally Posted by Gerald C Koch View Post
    There is no reason to believe that this developer would do any better with pictorial subjects than any conventional developer. It's was designed to measure film speed and was not intended as a general purpose developer. As far as the slight speed increase reported this can be easily obtained with a phenidone based developer.
    Actually it's close to other formulae in commercial production before the ASA speed system and it's chosen test developer were agreed on, Agfa 44 / Agfa Ansco (GAF) 17 is one of them. As you wrote in another thread 75-80gm per litre Sodium Sulphite is the optimum maximum level. When I used Adox Borax MQ commercially in the 1980's I supplied it to 2 commercial/advertising photographers who felt it was slightly better than D76.

    A Phenidone versions would give an increase over Adox Borax MQ, ID-68/Microphen fits into this category, that's 2 steps from D76.

    Ian

  4. #14
    Ian Grant's Avatar
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    AUTOPHEN

    That needs correcting it's the Axford Kendal PQ Fine Grain photo-finishing developer sold by Ilford as Autophen. It's a PQ variant of D76/ID-11 and had two different replenishers one for topping up and the other for bleed systems.

    Ian

    Quote Originally Posted by Gerald C Koch View Post

    Ilford AUTOPHEN

    Distilled water (50°C) …………………………………………… 750 ml
    Sodium sulfite (anhy) ……………………………………………… 100 g
    Hydroquinone ……………………………………………………………………… 5.0 g
    Borax (deca) ……………………………………………………………………… 3.0 g
    Boric acid …………………………………………………………………………… 3.5 g
    Phenidone ……………………………………………………………………………… 0.2 g
    Potassium bromide ………………………………………………………… 1.0 g
    Distilled water to make ………………………………………… 1.0 l

  5. #15

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    Thanks Ian, I've corrected my notes.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

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    Quote Originally Posted by Gerald C Koch View Post
    There is no reason to believe that this developer would do any better with pictorial subjects than any conventional developer (...)
    You are certainly right. But I'm curious to see the formula.

    Quote Originally Posted by Ian Grant View Post
    I have the formula somewhere along with the one used for the DIN standard (...)
    If you could find them, I would be gratefull.

  7. #17
    Ian Grant's Avatar
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    Quote Originally Posted by Gerald C Koch View Post
    Thanks Ian, I've corrected my notes.
    It's one of those mistakes from the Photo Lab Index that was perpetuated by countless other US publications. There were a series of articles in the BJP in the late 1950's early 60's that essentially chart the the evolution of Autophen from an early simpler PQ version of D76, the buffering was varied a few times before the final product. The articles were about things like testing effects of bromides, and the exhaustion so that they could design far better replenishment systems.

    Microphen must have come from the same research but Ilford claimed that it was an entirely new developer, rather than a simple PQ version of an MQ developer. ID-68 is inter changeable with Microphen.

    Microphen was sold in powder form with a replenisher, and in a wide range of sizes (mixed capacity), Autophen was available in larger sizes as a powder or as a liquid developer. Both were available in the same mid sized powder sizes. The recommended developing times were different and Microphen was stated to give an increase on the box speed.

    Ian

  8. #18
    Ian Grant's Avatar
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    Quote Originally Posted by Harold33 View Post
    You are certainly right. But I'm curious to see the formula.



    If you could find them, I would be gratefull.

    My notes say the ASA developer was the same as Adox Borax MQ, however there may have been a slight variation due to weight conversions. (numbers getting rounded up or down.

    When the ASA film speed system was being set up there were a few US film manufacturers and all would have had some input. Agfa Asco was by then under Government control, there was also Dupont (who later took over Adox). Presumably there were others.

    Ian

  9. #19
    Bill Burk's Avatar
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    Quote Originally Posted by Gerald C Koch View Post
    There is no reason to believe that this developer would do any better with pictorial subjects than any conventional developer. It's was designed to measure film speed and was not intended as a general purpose developer. As far as the slight speed increase reported this can be easily obtained with a phenidone based developer.
    It might not be better pictorially, but it's interesting to me to note that it may account for 1/3 stop speed difference when it comes to calibrating a sensitometer.

    But if we generally develop in D-76 1:1 instead of the standard ASA developer, wouldn't that mean we are generally losing 1/3 stop speed, and shouldn't we adjust our light meters accordingly?

    And as for the standard formula, if that is what one really needs for lab testing purposes, anyone is welcome to know it exactly by paying for the published standard document.

  10. #20
    Stephen Benskin's Avatar
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    This is the formula from ANSI PH2.5 - 1979.

    Click image for larger version. 

Name:	ASA Dev - 1979.jpg 
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    This is the formula for the Fractional Gradient Method as described in the Aug 1943 paper American Standard Method for Determining Photographic Speed and Speed Number, Journal of the Optical Society of America.

    Click image for larger version. 

Name:	Fractional Gradient - Dev - 1943.jpg 
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    BTW, I'd like to see someone substantiate the 1/3 stop speed statement. Let's try to support statements with facts and help reduce the propagation of myths and hearsay.

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