View Full Version : Rail lengths you'd want on an ULF?

10-12-2007, 11:21 PM
I'm working on a camera build with some friends, and we're trying to anticipate what rail lengths we'd like (it's going to be a hefty monorail design and will be extensible by coupling rails). This will be primarily a 12x20 with 8x20 reduction, but we have entertained the idea of building 7x17 and/or 11x14 reductions for it as well. We've been throwing numbers around, and so far have thought of perhaps two 18" rails, or a 24" + 20" + 10" rail setup (this latter giving the options of 20", 24", 30", 34", 44" and even 54" depending on how you connect the rails).

What would you do to economize on weight / number of rails, but still have a versatile camera (and minimize being poked in the chest and/or having the rail in the way of wider shots)? What extensions are most useful? We don't have any lenses, though I do have a 12-21-28" turner reich triple which I've heard might cover with the longer focal length single elements (21 and 28"). Otherwise we might look into some of the bigger process lenses, dagors, etc - basically whatever becomes available.

What would be your ideal monorail setup for a camera of this size though?

David H. Bebbington
10-13-2007, 01:28 AM
You are no doubt aware of the "conjugate distances" formula:

1/u + 1v = 1/f

where u = subject distance, v = image distance, f = focal length.

According to this, focusing to 1 meter with a 20"/500 mm lens needs 39"/1meter/ bellows extension, focusing to 2 meters needs 26.22"/666 mm. It is your decision - with ULF, there must be a compromise between versatility and sheer bulk and weight. A short rail would only be useful with a wide-angle lens (around 8 or 9"?). I personally have nothing bigger than 8x10", and a 600 mm bellows seems quite a handful in the field! As regards weight, unless you use super high-tech materials, it's going to be hard to make a light camera which will take really heavy lenses.



David A. Goldfarb
10-13-2007, 07:16 AM
I guess it depends on the camera. I'm happy with my relatively short, double extension Korona 7x17", because it's light and portable, and I see it mainly as a wide-to-normal panoramic camera for landscapes, some still lifes with a normal lens maybe, and full length portraits, all of which I can do with the extension I have. 11x14" I think of more as a portrait format, so when I had the bellows replaced on my camera, I wanted the maximum length for the rail I have (around 34", if I remember correctly--about 10" longer than the original bellows on the camera).

Check the classifieds here and at the LFphoto.info forum for Tri Tran's 20x24" Chamonix, which has a detachable bellows extension. I think for a convertable camera, that could be an ideal solution.

If you wanted to build a monorail camera around the Sinar P/P2 system, instead of reduction backs you could make format conversion kits, each consisting of a back that clamps to the post on the rear standard bearer and a tapered bellows that could be fixed to the back and would attach to the front standard, which is the same for all formats, so you would have an appropriately shaped bellows of suitable length for each format. And if you occasionally need more bellows, you just add another front standard (usually you would use an F/1/2 front standard as the intermediate standard), more rail, and a standard 4x5" Sinar bellows between the intermediate and front standards.

Nick Zentena
10-13-2007, 08:31 AM
Hasn't somebody made zoomable rails?

Roger Hicks
10-13-2007, 09:00 AM
Hasn't somebody made zoomable rails?
Linhof and Toho (at least), but not in ULF. It might be worth looking to see how they did it, but then again, it might not: the sections are very interesting, especially with the Linhof.

Personally I wouldn't touch a ULF monorail. An 8x10 monorail is pig enough, always ready to topple: I normally hang mine upside-down from a studio stand, rather than using a tripod. But my 12x15 Gandolfi tailboard goes on quite modest tripods, right way up.

David A. Goldfarb
10-13-2007, 09:52 AM
Arca-Swiss also has collapsible rails, but with the Sinar system it's very easy to attach additional rails, intermediate standards and bellows if needed, and if you just need a short rail, you don't have to transport the weight of the extra rails, etc.

My 8x10" P came with what seems to be a custom extra-long bellows (it was from a commercial food studio, so it was used mainly for still life), so I've got 40" or so of rail to use it. On the occasions that I've tried that, I've generally used two tripods.

Nick Zentena
10-13-2007, 11:14 AM
My big Cambo is setup for two tripods also. Supposedly the front standard could be replaced with one from a 5x7 or 4x5 camera and the bellows made even longer. The stock 8x10 bellows are already close to 36" I think. I've seen a few of the 5x7s for sale but they often go for idiotic prices. Awhile back somebody paid over $200 for one with bad bellows. I guess the same way somebody could attach my 8x10 back to a smaller front end I could attach my 8x10 front to a bigger custom rear end. OTOH the thing out weighs me now. I'd hate to imagine with an ULF rear standard.

Dave Wooten
10-13-2007, 02:32 PM
For myself, I would not be as interested in making it lightweight as I would be in having the strength and stability....My 8 x 10 Toyo G has 1200mm bellows and is quite strong. I like the Toyo rail system, the dia of each section is larger than most, also it can be put together in rail sections as short as 6 inch (which is what I transport the system on)...

The advantage (IMNSHO) in designing a ulf camera on a rail system is that it could be designed modular and you do not have to lift the full weight up on the tripod, it can be assembled and transported in sections.

I like the ability to use the long lenses i.e. 600, 750 and 1000 mm-1200 mm, and have been slowly acquiring equipment to do so in 8 x 10 and 14 x 17.

If one is to use only the wide aspect of ULF a simple plywood box camera with the appropriate box length (i.e. Zero Image) will suffice, saving in some instances thousands of dollars. A 12 inch or less naugahyde bellows for focusing back or front will suffice. For 14 x 17 I chose to go with the Wisner for the added bellows length and the overall strength of the camera at extension-

A 2 rail system would be nice I think also a quad pod instead of a tri pod, more of an aluminum ladder type of arrangement--Roger's idea of hanging the camera rail system is a good one and would work well I think with a quad pod set up.

10-13-2007, 08:52 PM
Personally I wouldn't touch a ULF monorail. An 8x10 monorail is pig enough, always ready to topple: I normally hang mine upside-down from a studio stand, rather than using a tripod. But my 12x15 Gandolfi tailboard goes on quite modest tripods, right way up.

Our thinking is that we would actually economize on materials and simplify the building while gaining some sturdiness and extension versatility by going with a monorail design. By monorail I mean something like a 6" wide by 1.5" thick section - almost like a narrower, slightly chunkier flatbed, rather than a square rail or something. We'll keep the center of gravity as low as possible, not like some of the really tall studio monorails.

When folded down and locked in place onto a very short rail, it would probably be about as portable as any field camera. Of course any 12x20 is going to be a bit of a beast anyway. The benefit to a rail design is that longer rails can be removed and stored separately so you don't have to lug them as part of the unit, as you would with something like a triple extension bed camera (wherein you either have to have shaky little light extension pieces, or a lot of bulk permanently affixed to the camera). You can also slide the tripod mounting point very easily, and add an additional tripod mount if you're using an extension that requires a second tripod.

So would 20 + 24 + 10" rails (assemblable in any combination) sound reasonable?

You'd have 20", 24", 30", 34", and 44" possibilities with just two rails. 54" with all three, though I doubt we'll build a bellows that long unless we decide to come up with an intermediate third standard.

10-13-2007, 10:23 PM
I guess a 355mm G-Claron or 450 Nikkor will cover 12x20, but how wide do you want to go with that format? A ~600mm (24") lens would be normal. I'm assuming you are looking to use this camera in the field for landscape work rather than in a studio. I doubt any rail smaller than 24" would be of much use unless you envision using the smaller ULF formats most of the time or doing work only at infinity with wide lenses. The bulk and weight is going to be in the camera, not the rails. I'd probably go with two 24" rails or a 24" + 30" set and think about building a second smaller camera if you really think you would be using those formats a lot. A 7x17 system would be a lightweight compared to hauling around a 12x20 with a reducing back and holders and 2 or 3 rails.

One camera can't do everything well.

10-13-2007, 10:46 PM
Thanks, smie. I'll pass your comment on to my friends.