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  1. #1

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    Fuji Acros in Pyrocat-HD

    Below is some BTZS data derived from testing Fuji Across, 120 size, in Pyrocat-HD with what I call extreme minimal agitation.

    For those not familiar with Fuji Acros it is a very fine grain, very high resolution medium speed film, of ASA 100. When used with a high quality medium format 6X7 or 6X9 camera and lens, and exposed on a tripod, this combination is capable of results equal to, or in some cases superior, to 4X5 LF when using higher speed films.

    The Pyrocat-HD dilution was 1:1:100, with development at 70F. The film was agitated vigorously for one one minute at the beginning of development, then for ten seconds at the one-quarter, one-half and three-quarter points of development. No pre-soak was used. The stop was 1/2 strength acetic acid, fixer was Formulary TF-4.


    When the step wedge negatives were processed and dried they were read with a densitometer (Blue Mode) and the curves were plotted with WinPlotter. The EF (exposure scale) in WinPlotter was set to 1.40, which should give good results with VC silver gelatin papers. For scanning I would recommend reducing development times by about 15%.

    Results below.

    SBR Time
    9 11 minutes
    10 14 minutes
    11 20 minutes
    12 29 minutes

    TIME Average Gradient (Approximate CI)
    10 0.5
    12 0.55
    14 0.60
    16 0.65
    20 0.70
    24 0.75
    26 0.80
    30 0.85

    The tests indicate that the EFS (effective film speed) of Acros is about 115 with this developer and type of agitation, and is virtually the same from SBR 9 through SBR 6 so no change of development is indicated for Plus or Minus develoment within these limits.

    Sandy King
    Last edited by sanking; 02-09-2008 at 12:22 PM. Click to view previous post history.

  2. #2
    keithwms's Avatar
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    Wow thanks Sandy, very powerful info.
    "Only dead fish follow the stream"

    [APUG Portfolio] [APUG Blog] [Website]

  3. #3

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    Quote Originally Posted by keithwms View Post
    Wow thanks Sandy, very powerful info.
    Hi Keith,

    Thanks. Give the combination a try. You will find it very hard to beat for making prints up to 18X22 or 18X24 from 6X7 and 6X9 negatives. At this size the prints should be very sharp and have a nice tight grain pattern.

    I find the Acros just slightly better than Tmax-100. Acros grain is finer, sharpness about the same.

    Sandy

  4. #4
    malinmalin's Avatar
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    I'll sure give it a try soon!
    Sandy, what was the dev time you used?

    jf
    jf
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    "The fact was I had the vision...I think everyone has...what we lack is the method." J.Kerouac

  5. #5

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    Quote Originally Posted by malinmalin View Post
    I'll sure give it a try soon!
    Sandy, what was the dev time you used?

    jf
    I used several development times in order to plot the data. What you need to do is match the subject brightness of the scene and develop for the time indicated. If, for example, you are developing for printing on VC silver papers, use SBR of 7 (N) and the time indicated. If your scene is very low contrast, use an SBR of 6 and develop for the time indicated. If the scene is high contrast, use an SBR of 8 or 9 and develop for the time indicated.

    Sandy

  6. #6
    malinmalin's Avatar
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    Quote Originally Posted by sanking View Post
    I used several development times in order to plot the data. What you need to do is match the subject brightness of the scene and develop for the time indicated. If, for example, you are developing for printing on VC silver papers, use SBR of 7 (N) and the time indicated. If your scene is very low contrast, use an SBR of 6 and develop for the time indicated. If the scene is high contrast, use an SBR of 8 or 9 and develop for the time indicated.

    Sandy
    I should read before replying!
    Need some more coffee

    Thank you!
    jf
    jf
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    "The fact was I had the vision...I think everyone has...what we lack is the method." J.Kerouac

  7. #7
    Buster6X6's Avatar
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    Thanks Sandy
    It is my film of choice for 6X6 and 6X9. Would the data be the same for Pyrocat-MC which I use primarily. Thanks in advance.

    Greg
    Looking is a gift, but seeing is power.

    Buster6X6

  8. #8

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    Quote Originally Posted by Buster6X6 View Post
    Thanks Sandy
    It is my film of choice for 6X6 and 6X9. Would the data be the same for Pyrocat-MC which I use primarily. Thanks in advance.

    Greg

    Yes, in developing -MC I adjusted the formula to give development times that are almost the same as for -HD.

    Sandy

  9. #9
    Buster6X6's Avatar
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    Thank you Sandy.I have been using this combination for over a year now and it is great.

    Greg
    Looking is a gift, but seeing is power.

    Buster6X6

  10. #10

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    fuji and pyrocat mc

    sandy-been using this combo for quite some time now except no minimal agitation...have made some of my best prints to date along with graded paper...
    always a thanks for your thorough work.
    Best, Peter

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