I have been involved in revamping a mono rail as I recently acquired a 300/500 lens & noted to my dismay that I couldn't extend to 1:1 macro with the 3oo mm. So the problem of extension & bellows. Looking at bellows construction I came across a photo of an 8x10 field wearing an extended bellows, noting the addition of velcro strings to pull (gather) folds thereby vaguely giving usable (self-supporting) shape to the bellows. I had thought about adding a riser & bellows rather than having to deal with weak bellows having to be supported.
Any other suggestions or thoughts on either design?