Seeking lens info

Discussion in 'Large Format Cameras and Accessories' started by eSPhotos, Jun 22, 2011.

  1. eSPhotos

    eSPhotos Member

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    How can you tell the image circle size of a lens?
    I am in the market for a LF lens for 4x5 view camera that I am planning to build.
    Are there web sites for lens specs?

    Also, what would be the ideal image circle for the 4x5 with a 15 degree max shift.
    Thanks
     
  2. Dan Fromm

    Dan Fromm Member

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    There are many lists posted on the 'net. Here's one: http://graflex.org/lenses/lens-spec.html And here's a Google query that will find many: http://www.google.com/search?q="lar...fficial&num=100&lr=&ft=i&cr=&safe=images&tbs=

    There are many many lenses so all of the lists are incomplete. Many are compilations of manufacturers' claims published in catalogs. These are often, especially for older lenses, exaggerated, sometimes greatly exaggerated.

    Shift is measured in linear units (miles, yards, feet, inches, ...), tilt in degrees. Which do you mean?
     
  3. Whiteymorange

    Whiteymorange Member

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    This might be helpful.
     
  4. eSPhotos

    eSPhotos Member

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    Thanks Dan for the sites. A few bookmarked.

    Re shift, I was referring to angle of offset. 15 degrees of a 150mm FL is equal to approx 40mm (1.5 inches) up/down.

    Based on simple calculation, I need a lens that covers 8" x 4" rectangular coverage or 9" (230mm) image circle.
    Does this sound right?
     
  5. eSPhotos

    eSPhotos Member

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    Thanks
     
  6. mjs

    mjs Member

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