Gosh, this is a good old thread !
Looking at Dianna's picture that got it all rolling,
there are a couple things that we haven't hit on.
Today, I was working with an 8x10 Portrait Camera,
and I see one thing right off:
If this was made on an 8x10 plate, I'd guess the focal length is about 18" (480 mm).
It looks like it was shot at f/8, or thereabouts, from about 8 feet away.
Maybe a 24" lens.
Maybe there was a little rise on the lens, and maybe a little tilt down,
with the back adjusted to get the image plane corrected.
Not MUCH movement, just enough.
If you shot this on 35mm, a 60mm would be good, but to get the limited depth of field,
you'd need an aperture of (480/8) 60mm. With a 60mm lens, that would be (60/60) f 1.0.
You could back off to 135mm, and shoot at (135/60) f/2.2. Much better. But stopping down to f/4
would completely lose the effect.
Well, that's just cup of coffee after dinner speculation.
Cool picture.
Nicole: I'll bring the 135/2 to Toronto...
.