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  1. #11

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    Quote Originally Posted by Flotsam
    I seem to remember that there is an article on APUG that covers this.
    I tried to find it...I couldn't

  2. #12

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    Quote Originally Posted by Flotsam
    I seem to remember that there is an article on APUG that covers this.
    Try this link: http://www.apug.org/forums/article.php?a=3

    Dr Bob wrote it.

  3. #13

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    Quote Originally Posted by JHannon
    Try this link: http://www.apug.org/forums/article.php?a=3

    Dr Bob wrote it.
    Nice. Thanks for the link

  4. #14
    Photographica's Avatar
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    I've had the notion that a color analyzer and something to calibrate with (step tablet) would make a good densitometry arrangement. The idea occurred when at an auction recently I witnessed 3 analyzers sold as a lot for $5.00

  5. #15
    Dan Henderson's Avatar
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    The latest edition of Photo Techniques magazine has an article describing how to use a film scanner to read negative densities. You also need a transmission step wedge and a program that you can download free from the internet. I just read it and haven't had time to try it yet, but will as soon as I can get my hands on a step wedge.


    web site: Dan Henderson, Photographer.com

    blog: https://danhendersonphotographer.wordpress.com/

    I am not anti-digital. I am pro-film.

  6. #16
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    The cheapest way to do this is to pick up a Stouffer 21-step transmission density tablet for about $9 from a graphic arts supplier or Bostick & Sullivan. Surround the thing with black opaque paper and place that over a piece of blank film (unexposed but developed) of the type you're testing. Take it to a light box and along with your test negative(s) and a couple 3x5 cards with paper-punched holes in them, and visually compare the density on your test negative to the steps on the tablet.

    This is remarkably accurate. The steps of the tablet increase in an increment of 0.15 and usually have a base density of for step 1 of about 0.05. By placing the tablet over a piece of blank film having only fbf density, you can read net densities very easily with this method.

    Another way to achieve the density comparison inexpensively is to purchase a 0.10 wratten neutral density filter and use it on a blank piece of film to compare visually to a test film. This is less versatile however since it will only allow you to identify the speed point density of 0.10 above fbf.

    Henry Horenstein's basic photography text goes over the latter test and Sullivan & Weese's New Platinum Print book outlines the former. IIRC, I believe S&W originally got the idea from an early issue of The World Journal of Post-Factory Photography.

    Joe

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