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  1. #1

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    Texas Chrysotype Process

    I am Richard Puckett, introducing my Texas Chrysotype process, which was presented in the March/April 2012 issue of View Camera. If you have not got access to back issues of VC, visit unblinkingeye.com.

    The process is characterized by:

    • Fine grain
    • Excellent Dmax and Dmin with good tonal separation between the two extremes. In other words, true continuous-tone images
    • Dry print out. You determine correct exposure by direct examination.
    • No humidification of paper. For the January 2012 proof of process demonstration to members of the Austin Alternative Processes Group, I used Arches Platine stored in a closed plastic bin with 4 pounds of silica gel. RH was 29%.
    • Economical 10% gold chloride solution.
    • Key is the addition of ascorbate to ammonium ferric oxalate. Some of the gold precipitates out to form a foundation that smooths out the image and greatly extends its tonal range.
    • Absolutely repeatable. Make print after print of the same negative.
    • Standard clearing as for ziatypes.
    • Contrast control by various means.


    I have put six samples up in my APUG album. Incidentally, I have developed a (significant) variation on the process that makes it equally simple to print with palladium and platinum, as well as gold and platinum. I will be announcing that process later this year in another magazine article.

  2. #2
    MDR
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    Thank you for the Info, how does it compare to the other Chrysotype process in terms of image tone?
    Dominik

  3. #3

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    Hello Richard and a warm welcome to APUG. Looks like a wonderful process.

    Jeff

  4. #4

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    How it compares to other processes

    Dominik,

    I was trying to print my texas revolution negatives using the traditional ammonium ferric oxalate/gold chloride approach, both Ware's and Sullivan's ziatype with gold instead of palladium. I expect you know what that looks like. I could not bear to print my negatives as grainy, gritty, contrasty red images. With ascorbate added to the afo, a base of gold precipitates out onto the paper and eliminates grain while smoothing out tonal separation and extending the range out to between 9 and 11 stops, depending on the paper you use (wider range with clearprint cotton rag vellum; narrower with Arches Platine). Your negative is also important: negatives exposed for printing on silver gelatin are better than ones exposed for Pt/Pd printing. Comparison? If the other processes were 35mm HP5+ printed to 8x10, the texas chrysotype would be 35mm Iflord Pan F+ printed to 8x10. I don't know if the below image can be enlarged; larger one is in my album.
    Click image for larger version. 

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  5. #5
    Sirius Glass's Avatar
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    Welcome to APUG
    Warning!! Handling a Hasselblad can be harmful to your financial well being!

    Nothing beats a great piece of glass!

    I leave the digital work for the urologists and proctologists.

  6. #6

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    Versatility of the chrysotype

    Hello, Jeff and Sirius,

    Yeah, it is neat! I've been invited to present it at APIS in 2013. Good things about this process are:

    • Fine grain: as in none up to just apparent (depends on how much ascorbate you add to afo)
    • Controllable contrast: boost contrast by substituting a drop or two of plain sodium ferric oxalate for the afo-c); reduce contrast by sizing paper with arrowroot starch or gum arabic (clear gum arabic prints with 2% HCL acid!), or by substituting platinum or palladium for gold on a drop for drop ratio, or just use rag cotton vellum
    • Full tonal range: retain shadow detail and also highlight detail with straight afo-c and 10% gold
    • Economical: gold for an 8x10 costs $2.25 at current price; about $1.40 for my whole plate negatives
    • Dry print out by inspection -- you brush on the sensitizer and place the print in a dark, dry place and when fully dry, print
    • First bath is usually ice water to keep the print from darkening further
    • Clear in usual acid/water/edta/water/hypo clear/water/edta/water succession of baths


    With this process, I can make a lovely print on the spur of the moment...

    Regards,
    Richard



 

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