Re: Maximum Extension Tube Length

[Mark Cassino]

I've shot with over 300mm of extension tubes, using a 50mm reverse mounted on a 135mm (magnification was >10x life sized on the film.) The practical problem is preventing unsharpness due to vibration - it's a pretty ganglely rig. Stack it so everything is vertical, douse the lights and use a flash for exposure (TTL won't work so you'll have to work up effective aperture and calculate flash distances). The flash acts as a very fast shutter and counteracts the effects of vibrations. Still a tough rig to work with.

Somewhere in the PUG archives is a photo of a snowflake I took with that setup.

- MCC

At 10:39 PM 1/10/01 -0800, you wrote:

Is there any theoretical or practical limit to the length of
extension tubes?  Could a 150mm - 200mm length be used with a
200mm macro lens without any image degradtion?
--
Shel Belinkoff
mailto:[EMAIL PROTECTED]
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Mark Cassino

Kalamazoo, MI

[EMAIL PROTECTED]

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Photos:

http://www.markcassino.com

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