Re: Tilt bellows

John Taylor [The Banshee] (rphjt@minyos.xx.rmit.OZ.AU)
Tue, 2 Feb 93 07:59:18 +0000

>Tilt lenses for 35mm are available, but they are very expensive, as
>much as some lower end camera and lens combos. They give a limited
>degree of perspective control. But your idea is a good one; the
>scheimpflug effect (yes that's really it's name) will allow some
>adjustment of focal plane. The trick is to bring an imaginary line
>from the back to front of the subject and the lens, and the focal plane
>of the camera into alinement so that they covererge at an imaginary
>point below the camera. It works.
>
>That word should be "converge" in the line above. It's awfully early.
>
>J. Del Col

We have a couple of old "process" cameras in our lab which do exactly
this. Basically, they made up of a large bellows, a lens/shutter
combination on one end and a film plate holder on the other (sheet film,
not 35mm...) The tilt and position of each end-plate of the bellows is
independent, so you can basically have any configuration you like.
Although I've never used one, you are supposed to be able to correct for
tilted focal planes, correct perspective (ie. take a photo of a
building from an angle, but make it look like you took it from straight
ahead (I think...) ) etc. etc. I think that they are expensive (if
they still make them) and look tricky to use (no exposure metering,
awkward focusing on a ground glass plate (no split prisms or microprisms
here!) They also are fairly heavy and bulky - you need a reasonably
strong tripod to support one - definitely not hand held work...

BFN

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| John Taylor [The Banshee] | Royal Melbourne Institute of Technology |
| rphjt@minyos.xx.rmit.oz.au | Department of Applied Physics |
| MOKING IS A HEALTH HAZARD. | Melbourne, Victoria, AUSTRALIA |
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