Extension Cone for L.F.Camera

[mario_mab]

Hello,

 

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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?

 

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Thank you.

[bob_salomon3]

Wista makes them for their cameras and Linhof cameras.

 

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The drawback is that the rear element of the lens has to be

small enough to fit into the extension ring (not a cone).

 

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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.

[alpshiker]

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.

[mario_mab]

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).

 

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Thanks for your help.

[bob_salomon3]

The Wista extensions screw together to make different lengths.

This would be difficult with a cone.

 

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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

[doremus_scudder1]

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)