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?