I have been thinking about building a ULF camera for sometime, but my 12 hour days as a basic cancer researcher kept me from investing much time into this. However, I took a vacation recently and here it is. A 12x20 camera converted from Arca Swiss parts. Basically, it uses the front and the rails of an Arca Swiss F basic connected to two parallel Arca rails by a 3/8x3x12 inch aluminum plate. The 12x20 camera back sits on the two rails via two Arca function carriers. To give enough front raise, I raised the front part of the camera by a 1.5 inch oak block and a 1/4 inch aluminum plate. In the final configuration, the lens will be centered relative to the 12x20 back. This camera weighs only 21 lbs and is as rigid as a Arca Swiss 4x5.I have no doubt hat this set up will support 20x24 if I want to go that size. It goes horizontal and vertical. The best thing is I can virtually use any format I want. All I needed is attach a dovetail under the camera back. This is a great feeling! Why? I can still use my Arca Swiss 4x5, Arca 8x10. The only other system that is so convertible is the Keith Canham cameras. But the Arca conversion has rear shift, tilt and swing, which few ULF has.

http://www.pbase.com/aria1117/ultra_...format_project

james