Quote Originally Posted by John Bartley
Ok, with that settled, here's my thinking;

Any time I take a "normal" (no radical movements) picture from a "normal" (not right close up) distance, my lens usually appears (I've not measured it) to be set close to it's focal length from the film. If this is the case, then if I am only using one lens, the need for a travelling lens stage pretty much goes away and all that's required is a small amount of fine focussing movement? This means that a basic landscape camera can pretty much be a box as long as the box is the right length for the lens.

Sooo ... if I wanted to take pnoramic landscapes on a 10" x 24" negative, all I would need is a 10"x24" film holder, a ground glass holder, a lens that will cover 10"x24" (26" circle) and a light-tight box of suitable length for the lens ????

Am I nuts ?? (don't answer that )

Of course you're nuts. So what?

You've characterized where all lenses of "normal" (not telephoto, not retrofocus) construction sit when focused at infinity. More-or-less 1.0 * f from the film plane. So what? And why limit yourself to lenses of normal construction? I mean, if you're contemplating a relativley low-budget DIY project then lenses from aerial cameras should appeal to you.

Until you know the lens' focal length and how much closer than infinity you'll want to focus, you won't be able to calculate how much focusing travel you'll need. FWIW, my rule of thumb for lenses to be used at normal distances is that I want the lens to focus to 1:10; this requires focusing travel = 0.1f, max extension = 1.1f. Extension is film plane to lens' rear node, not to the lens board.

Cheers, have fun,