Double or Triple Extension?

Discussion in 'Large Format Cameras and Accessories' started by jmcd, Oct 30, 2002.

  1. jmcd

    jmcd Member

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    Would someone please compare the merits of a double- versus triple-extension design, in general terms, for 8x10? In what cases is one design preferred over another?

    I am now looking at the Gandolfi traditional, which is a double-extension design, with about 32" of bellows.
     
  2. David A. Goldfarb

    David A. Goldfarb Moderator Staff Member

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    Usually "double" or "triple" extension is considered with respect to the "normal" focal length for the format, so a typical double-extension 8x10" camera would have 24" of bellows and a triple-extension camera might have 36". This one that you are looking at is in the middle--a generous "double-extension" camera.

    The advantage of a shorter bellows is that it is lighter in weight and will compress smaller for use with ultrawide lenses--ideal for a field camera for landscapes and architecture, where wide lenses are commonly used and light weight is desirable.

    A longer bellows is attractive for portraiture and tabletop work, where you want higher magnification with longer lenses to increase working distance between the camera and the subject.

    Outdoors, long bellows extensions can be quite impractical, often due to wind and long exposures required at high magnification factors, not to mention the need to balance 36" of camera on a tripod that can be easily carried (if not two tripods or a tripod with a sidearm). In the studio and with studio lighting, this is not as much of a problem.

    A camera with 32" is a good compromise. It would let you use a lens of up to 20" or so easily for portraits and should have enough flexibility to let you apply movements with a 24" lens (not possible, if you really only have 24" of bellows). The widest lens you are likely to use with 8x10" is 110mm, and whether this is possible will depend on the specific design of the bellows and the standards. You may need a bag bellows (if the bellows is interchangeable) or a recessed lensboard for ultrawides.
     
  3. rogein

    rogein Member

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    </span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (jmcd @ Oct 30 2002, 12:59 PM)</td></tr><tr><td id='QUOTE'>I am now looking at the Gandolfi traditional, which is a double-extension design, with about 32" of bellows.</td></tr></table><span id='postcolor'>
    I've used/owned a Gandolfi Traditional and found that I had no problems with movements using a 9 1/2" lens. Because the Traditional employs a sliding lensboard what you can't coax out of the bellows you get easily make up the difference by using the sliding lensboard. On the long end a 24" lens was no problem either. Again because of the Traditional's front standard design you can get an extra couple of inches by extending the standard past the front focus rail. All in all a great camera - it's unfortunate they've recently had a price increase.

    Good luck!

    Cheers,
    Roger...