Imagon 200-250-300 H values info

Discussion in 'Large Format Cameras and Accessories' started by Willie Jan, Sep 12, 2006.

  1. Willie Jan

    Willie Jan Member

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    Hi,

    i did find a book from Alfons Scholz "Lichtbilder mit dem Imagon" which has a table with the calculated H values to F values.

    lens 200 lens 250 lens 300
    H 5.8 - H 7.7 F7.3 - F9.3 F7.7 - F9.6 -

    H 7.7 - H 9.5 F8.9 - F11.3 F9.2 - F11.6 F9.1 - F11.5

    H 9.6 - H 11.5 F10.7 - F13.6 F11.1 - F14.1 F11.0 - F14.0

    He explains that the H values work when you go for the shadows, but if you have to work with the highlights (slides) the H values would be to low so the 2/3 stop of difference could be visible on the slide.

    Maybe this is information for someone.
     
  2. Clueless

    Clueless Member

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    Have to confess...I am Clueless as to how to use those numerical relationships.
     
  3. Willie Jan

    Willie Jan Member

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    always fine when spaces are deleted...

    lens 200
    H5.8 - H7.7 = F7.3 - F9.3
    H7.7 - H9.5 = F7.7 - F9.6
    H9.6 - H11.5 = F10.7 - F13.6

    lens 250
    H5.8 - H7.7 = F7.7 - F9.6
    H7.7 - H9.5 = F9.2 - F11.6
    H9.6 - H11.5 = F13.6 F11.1

    lens 300
    H5.8 - H7.7 = -
    H7.7 - H9.5 = F9.1 - F11.5
    H9.6 - H11.5 = F11.0 - F14.0
     
  4. archphoto

    archphoto Member

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    Looking for

    Dear forum members,

    For a project I am looking for see-thru scans of the H-plates of the 200 and 300mm Imagon lenses. In Dutch: doorzichtscans van de zeefdiafragma's.

    I want to use these to drill holes in the aperture-plates of the latest Lensbaby so I get a Baby-Imagon for 35mm and DSLR.
    Can anyone help me ?

    archphoto@aol.nl