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otzi
10-Nov-2007, 00:08
I am seeking folks experience with the use of Lens extension tubes and or Rear extension frames found with some camera makes. How does this effect movements and general usability. Are they a poor option against getting a camera with longer bellows range, if one could?

While on the subject, what do photographers feel about tele lenses, generally. A last resort to gain length and or weight saving or a genuine love of the design. How is this rationalised against loss or difficulty od movements.

Otzi

Doremus Scudder
10-Nov-2007, 03:41
Ötzi,

Grüß' Di!

I made an extension lensboard (about 9cm) for my Wista DX to make using a 300mm lens possible. It works great, but since the lens is well forward of the planes of movement on the front standard, tilting and swinging the front is a bit trickier. It takes another iteration or two to get the correct focus and, if you swing or tilt too far, the lens can vignette (theoretically at least).

That said, I've never had a problem with vignetting and it is only a bit more trouble to use the swing and tilt on the front.

I used masonite (dünne Spannplatte) backing from an unused picture frame, wooden supports and small screws to build mine. The commercial ones I see from time to time are great though, and many have the capability to add length as needed. For me, using the extension lensboard keeps my kit small and flexible: I can use a 300mm lens on a 1.5 kg camera with only 300mm of bellows draw and, with a recessed board, can easily use a 90mm.

Hope this helps,

Freundliche Grüße,

Doremus Scudder

Brian Ellis
10-Nov-2007, 10:05
I assume the extension frames you're talking about are the kind often found on older cameras. I've owned an 8x10 Kodak 2d and an 8x10 Agfa Ansco, both of which had those kinds of rear extension frames. The one on the 2D was removable, the one on the Agfa Ansco was permanentaly attached to the camera and was raised or lowered by a hinge system. Both worked fine on my cameras without any major problems. The removable frame on the 2D added an extra few minutes of time spent in putting it on and taking it off, plus the gap between the camera back and the frame made the total setup not quite as sturdy as a camera without the frame. The permanent frame on the Agfa Ansco eliminated the time problem but caused the camera to be a little more cumbersome to backpack. But overall both worked well.

If you're thinking of a 2D make sure the number on the frame matches the number on the camera back where the frame attaches. Kodak made each frame to mate with a particular camera. If you get a homemade job or a frame from another manufacturer or even a frame from another 2D it may not fit as well as the one Kodak originally made for the camera.

C. D. Keth
10-Nov-2007, 10:39
The main annoyance to me is in using some movements with them. Use front tilt in a landscape as an example. The further the lens is from the axis of tilt, the more of a pain it is to use that movement because you have to refocus so much. You may even have to mix some front rise into the equation because the lens dropped down so much. Then you run into the problem of vignetting.

I think I would be fine using an extension board for a lens that is just out of the range of your camera. Otherwise, I would see if a longer bellows is available.

otzi
11-Nov-2007, 23:25
Yes thanks guys. I am trying to do my homework before buying a compact Clam shell. With both the Toyo A and the Wista options in my face. Both offer back extenders of 100 and 90 mm respectively and of course tubes are available also. I just don't have experience with these items.

I also don't have tele experience and wonder about their convenience. The clam shell idea is only for housekeeping when bundling, travelling and general auto storage. I stand to be corrected.

Bob Salomon
12-Nov-2007, 03:44
Yes thanks guys. I am trying to do my homework before buying a compact Clam shell. With both the Toyo A and the Wista options in my face. Both offer back extenders of 100 and 90 mm respectively and of course tubes are available also. I just don't have experience with these items.

I also don't have tele experience and wonder about their convenience. The clam shell idea is only for housekeeping when bundling, travelling and general auto storage. I stand to be corrected.

Wista does not have back extensions. They have extension lensboad sets and extra tubes for it and bed extensions to extend the front extensions. That do not change the lens position on the board.

otzi
12-Nov-2007, 04:05
Well I certainly got that wrong! To take it a step further then. How convenient is it to use,exchange or install these alternative front standard accessories on the Wista?