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View Camera 4x5 lens on a 2x3 camera

 
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chiefcoastie



Joined: 05 Jan 2005
Posts: 8
Location: New york City

PostPosted: Mon Jul 09, 2007 8:24 pm    Post subject: View Camera 4x5 lens on a 2x3 camera Reply with quote

Can anyone advise on a question about switching lenses on different format cameras? I have a 4x5 Super Graphic which has a Graflex 135mm lens and a Graflex 250mm lens. My question is, can I use these lenses on my 2x3 Crown or Speed Graphic? I have seen 250mm lenses on ebay for 2x3 cameras. Must I use lenses specifically for the 2x3 format.
Thanks in advance.i
Anthony
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ImageMaker



Joined: 20 Jun 2006
Posts: 93
Location: North Carolina

PostPosted: Mon Jul 09, 2007 11:15 pm    Post subject: Reply with quote

Generally, you can use any lens made for larger formats on the smaller camera, with two limitations: first, that the lens has to be physically small enough to mount on the smaller camera's lens board and the rear elements pass through the opening in the front standard, and second, that the bellows is long enough to focus the lens at infinity and as much closer as you need to get with that lens.

The latter limitation is the one likely to cause hate and discontent if you try to put a 250 mm lens on a 2x3 camera; some models of 2x3 Graphic camera (such as the Century) didn't have enough bellows draw to focus to infinity with lenses longer than about 210 mm, and 180 was really the practical limit to have enough additional travel for focusing to portrait distances. A lens with "tele" in the name would be the exception, as those lenses are designed to require less draw than their effective focal length would indicate. The earlier "Miniature Speed" and 2x3 Pacemaker Speed, as I recall, had similar bellows extension to their bigger brothers, and would probably be okay with even a 250 mm lens.

In any case, it's easy to measure your bellows draw -- put the front standard at the end of the bed rail and extend the focus until you either run out of rack or just short of pulling the pleats out of the bellows (don't put too much stress on 40-70 year old leather), remove the lens board, open the focal plane shutter if you have one, and stick a ruler in the front to rest on the ground glass; read it flush with the front surface of the standard or an unoccupied lens board and convert to millimeters if needed. Figure you'll want about 20% more than the focal length of the lens to allow for focusing closer than the horizon.
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Dan Fromm



Joined: 14 May 2001
Posts: 2156
Location: New Jersey

PostPosted: Tue Jul 10, 2007 10:07 am    Post subject: Reply with quote

ImageMaker has it almost all right, BUT it is very possible that the 250 mm "Graflex lens" you mentioned is a 250/5.6 TeleOptar. A telephoto lens requires less extension to focus to infinity than does a lens of "normal" construction of the same focal length. And in fact the 250/5.6 TeleOptar is the longest standard issue lens for 2x3 Graphics. So ask your 250 how much extension it needs to focus to infinity, and then you'll know whether it can be used on a 2x3 Crown/Century. Remember that the 2x3 Pacemaker Speed has a little more than an inch extension and a little more than an inch less minimum flange-to-film distance than the 2x3 Crown/Century. This because of space needed for the Speed's focal plane shutter.

Practically speaking, the longest lens of normal construction that can be used on a 2x3 Crown/Century is around 8". And reasonably close focusing will require full bellows extension. I don't think the camera will mind that, but some users aren't comfortable with it.

My compromise with this reality is to carry two 2x3 Graphics, a Century for my shortest lenses (38, 47) and a Speed for everything longer (58, 65, 80, ...) and for lenses in barrel. The longest lens that I can use on my little 2x3 Speed is around 300 mm, and that only if mounted on a short extension tube in front of a leaf shutter. Two 2x3 Graphics can be combined into a tandem camera. I've done this, the longest lens that can be used on it is around 480 mm.
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