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Thread: Question on image circles and angle of view

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    Question on image circles and angle of view

    I am considering moving over to a tech camera but am trying to understand image circles.
    If you buy a HR32 that has an angle of view of 107 degrees and an image circle of 90mm at F/11, you then have an IQ180 back that is only 53.7 mm wide, isn't your picture only going to be 63 degrees wide? That being said, do you then get added depth of field by having a wide angle lens that you can now shift with the larger image circle?

    Thanks for the help,
    Mark

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    Re: Question on image circles and angle of view

    The field of view quoted will be for a full frame MF sensor, so you'll get 107 degree field of view (diagonally) on the IQ180.

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    Re: Question on image circles and angle of view

    Thanks!

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    Re: Question on image circles and angle of view

    Quote Originally Posted by markymarkrb View Post
    I am considering moving over to a tech camera but am trying to understand image circles.
    If you buy a HR32 that has an angle of view of 107 degrees and an image circle of 90mm at F/11, you then have an IQ180 back that is only 53.7 mm wide, isn't your picture only going to be 63 degrees wide? That being said, do you then get added depth of field by having a wide angle lens that you can now shift with the larger image circle?

    Thanks for the help,
    Mark
    With a DSLR, the angular field of view is quoted as long side, short side or diagonal.

    With tech/view camera lenses the Angle of view is the relates to the lens image circle, and is not format related, and is the maximum diagonal angle of view you could get with stitching (assuming you camera allows enough shift).

    The Schneider info sheet quotes different angles of view for different apertures, so this is obviously not format related, and they quote maximum displacements (shifts) for different formats.

    The spare image circle is for perspective correction shifts and shift-and-stitch.

    A 40.2 * 53.7mm sensor has a diagonal of 67.08mm, giving you nearly 23mm for shift... I think a 90mm image circle gives you a 63MM square stitched image.

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    Re: Question on image circles and angle of view

    Oops. My bad.

    I got that totally wrong then?

    Sorry!

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