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  1. #21

    Join Date
    Aug 2012
    Location
    Austin, Texas
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    I'll have to email Byron Brauchli, who last spring guided his students through printing palladium mixed with AFFO(8:2%C), prepared by adding 8 drops of 2% ascorbic acid to 10 ml of 40% ammonium ferric oxalate, and this past summer through printing gold with AFFO(7:1%C), that the prints they made in his workshop were imaginary, hallucinations.

    I'll have to email the attendees at the 2013 APIS in Santa Fe that the prints I made before their eyes were hallucinations.

    I'll have to contact the members of the AAPG here in Austin to point out to them that the prints they made during my proof of process demonstration, with freshly prepared ammonium ferric oxalate and ascorbic acid mixed on the spot, don't really exist ... all because a self-righteous forum troll who pretends to vast knowledge and experience is incapable of preparing a simple solution of ammonium ferric oxalate and ascorbic acid. Or perhaps the person in question forgot to add the sodium chloride to the palladium? In any case, I won't watch that person's foredefeated attempts at printing, and will not return to APUG, because I innocently shared information with the OP only subsequently to be trolled. I mistakenly anticipated gentlemanly behavior in the forums.

    For those who are interested, I will within a few months be publishing on alternativephotography.com an article on sizing satin (polyester) for printing palladium (the sensitizer will be either ammonium ferric oxalate or lithium ferric oxalate to which 8 drops of 2% ascorbic have been added.) I chose polyester satin over silk and cotton because it does not yellow or stain and will last rather longer than either of the other two. I will also be publishing an article on developing out ruthenium with silver nitrate. And, I will be summing up either in print or on alternativephotography (or similar venue) my results from printing ruthenium, rhodium, iridium, and copper with gold, platinum and palladium (all using either AFFO[7:1% C], AFFO[8:2% C] or Lithium Ferric Ferrous Oxalate with 8 drops of 2% C, and with the mixtures of noble metals developed in traditional solutions). The most interesting result, to me, that I observed was ruthenium mixed with palladium: print out ranged from 15 seconds to 90 seconds, depending on how many drops of 2% ascorbic acid I added to 10 ml of 40% ammonium ferric oxalate (more drops resulted in faster print out, fewer in slower print out). This would be a boon to printers who live in extreme northern or southern latitudes as well as to those who live in cloudy zones (and all who choose not to print in a UV box). I don't think it of any use to one who lives in a cloud.

    I chose not to test the remaining two noble metals: mercury and osmium. I regard those two as simply too toxic to risk my physical well-being to obtain known results, with mercury, and what would likely be bluish images with strong Dmax, from osmium -- more or less a redux of adding iridium to palladium.

  2. #22

    Join Date
    Sep 2005
    Location
    Istanbul, Turkey
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    650
    Ok. As I promised, you'll find the scan of the pop pd test prints together, attached to the end of the message. (I scanned them together in order to eliminate exposure & settings differences that may happen between two separate scans...) I'll let people decide which one's is better technically - a picture is worth a thousands words. The test print with the ascorbic acid "contaminant" is on the right (marked with a C letter) and the test print made with the standard formula is on the left.

    Both prints were made on the same paper (COT 320 cut in half) using exactly the same workflow. 26C, 50% RH, air dried for 30 minutes, exposed for 16:00 minutes under a bank of BL tubes.

    Hope this helps.

    Regards to all,
    Loris.
    Attached Thumbnails Attached Thumbnails Ascorbic-comparison.jpg  

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