Extension Cone for L.F.Camera

greenspun.com : LUSENET : Large format photography : One Thread


I’m new in LF field and I’m in the process of buying my first LF camera. The camera I intend to buy is the Toyo VX125, which accepts lenses from 55mm to 300mm. But, what about if an extension cone is used to increase the distance lens-film plane? Do ‘Extension Cones’ exist? If yes, is there a disadvantage using them?

Thank you.

-- Mario A. (maab@nyc.rr.com), May 26, 2001


Wista makes them for their cameras and Linhof cameras.

The drawback is that the rear element of the lens has to be small enough to fit into the extension ring (not a cone).

With this system a Linhof Technika 2000 or Technikardan could use lenses from 35mm to over 400 on the 2000 and 500 on the Technikardan.

-- Bob Salomon (bobsalomon@mindspring.com), May 26, 2001.

Mario, I use the Wista extension tube (10 cm) on my Technika and it is very good. I even have some limited lens tilt possibilities. But I have a VX-125 too and, if the tube mounts without problem, the stability of the collapsible rail is not adequate for such an extension. I am presently looking for a way to replace the original rail by a plain rail and tripod block for the extended configuration. It should be okay then. Wista has two extension tubes. The one I use takes Wista-Linhof type lensboards.

-- Paul Schilliger (pschilliger@smile.ch), May 26, 2001.

That's interesting! I would have thought that for an ‘extension’ a form of a cone would have been less awkward then a cylinder. I assume that even using a lens on the recessed lens board reversed would extend somewhat the distance lens-film without the tilt- limiting factor, and may be effective too with the VX125 (hopefully).

Thanks for your help.

-- Mario A. (maab@nyc.rr.com), May 26, 2001.

The Wista extensions screw together to make different lengths. This would be difficult with a cone.

Linhof did make a tapered tube with a sfutter on its; end for macro photography. The taper allowed positioning a light close to the lens and the shutter accepts Leica mount lenses like the Apo Rodagon D series

-- Bob Salomon (bobsalomon@mindspring.com), May 26, 2001.

Mario, I built a extended lens "box" out of masonite with some small pieces of maple for corner reinforcements which I have been using on my Wista for years now. Time: a few hours: Cost: practically nothing since the materials were all scraps sitting around the place. It gives about 60mm of extension, but I could envision an even longer extension. With a modicum of woodworking experience, you could construct one as well. The movements which are limited with lens extensions are the front swings and tilts, and to a lesser degree, rise and fall, since the extension box can vignette with too much of either. I made mine as wide as possible at the back to limit this effect. Small amounts of swing and tilt are possible and I have had not vignetting problems with the rise and fall on my Wista DX. The back movements make up for the limitations when needed. In general, I would recommend using lens extensions, especially when weight is an issue because you can use a smaller, lighter camera. Regards, ;^D)

-- Doremus Scudder (ScudderLandreth@compuserve.com), May 26, 2001.

Moderation questions? read the FAQ