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Gundus
19-Oct-2014, 11:44
Hi,

I have a LF "point and shot" camera which have a limited bellows extension where I can mount up to a 120mm lense ( without extensions ).

I was interesting in buying a copal 0, 240mm lense, so in that matter I have to buy extensions tubes (another 120mm in tubes right?)

On ebay I saw some extension tubes that the guy sell them in 20mm, 30mm and 50mm sizes.

My question is, can I buy for exemple 2 x 50mm and 1 x 20mm? or perhaps 2 x 50mm and 1 x 30mm to have more margin (?) to focus on infinity?.

Do I have a limit to the lenght of the extension tubes that I can put on a camera?

Can I have problems with this 240mm copal 0 lense to focus?


Thank you in advance
All the best

Bob Salomon
19-Oct-2014, 13:00
Which 240mm lens. Many are in a 3 size shutter.

Ari
19-Oct-2014, 15:09
What about an extension lens board? One that extends farther out than normal.
Something like this: http://www.ebay.com/itm/New-Extension-Lens-Board-For-Linhof-Wista-Shen-Hao-4x5-Large-Format-Camera-/271186737287

George Hart
20-Oct-2014, 01:48
Yes it should be possible to fit the lens up as you suggest. In fact I have recently done just this for the Fuji 240A lens (I assume that's what you will be using, you do state the shutter size) on my Ebony SW23. This camera has a maximum extension of 157 mm, so adding 3 x 35 mm tubes means that the 240A can easily be focussed at infinity. And because this lens is so light, the setup is not unbalanced. Vignetting is absent.
The only problem I found was that internal reflections were obvious in the tube nearest the lens. So I made a couple of rough baffles from cardboard, sprayed with matt black, which do the job when fitted to the front and back inside of the back tube.

Gundus
20-Oct-2014, 03:25
Thank you for your replys.

Yes the lense that I would like to use is the Fuji 240 A. It's lightweight and as you pointed, I guess I will not have unbalanced issues.

So, base on your replys I'm willing to try this combination.

Thanks
regards

Dan Fromm
20-Oct-2014, 05:45
George, the extension tubes I used for my failed Baby Bertha project (read about it here: http://www.galerie-photo.com/baby-bertha-6x9-en.html ) were 4" PVC drain pipe. The tubes are translucent and their interiors were very shiny. Not what one wants an extension tube to be. I lined the tubes with flocked paper, used double-sided tape to attach it to the tubes. Not quite your approach, but it works.