Definition charts

Discussion in 'Silver Gelatin Based Emulsion Making & Coating' started by Photo Engineer, Dec 6, 2006.

  1. Photo Engineer

    Photo Engineer Subscriber

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    These are definition charts of an approximate grade 2 paper on 3 papers compared with Ilford MGIV.

    Conditions as in other post, but the ilford was exposed for 12" at f16 with a Magenta 30 which gives grade 2.

    The order is Baryta, Smooth, Watercolor and Ilford MGIV.

    PE
     

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  2. PHOTOTONE

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    Wouldn't this more correctly be called Resolution charts? Please correct me if I am wrong.
     
  3. Photo Engineer

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    Ok, lets call them Resolution Charts. I really don't care one way or the other. I called them Definition Charts.

    PE
     
  4. Photo Engineer

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    I was asked off-line why I had some charts that were white with black lines so here is the explanation.

    You do this test with both a positive and a negative chart (by whatever name you wish to call it). The chart above measures fill in or the creep of the black image through adverse edge effects or image scatter into the white bars. The other chart measures spread, or the creep of the black bars into the white background.

    Due to the differences in exposure and chemical effects, each type of chart gives a subtly different result. I ran both types of test but just posted the chart with the white bars.

    PE