scenic_man wrote:
I recently purchased a second-hand Mamiya M645,
together with a boatload of equipment.

The manual that came with it says "M645 J" on the cover.
However, I have noted minor discrepancies here and there.

One that has my attention at the moment
is a rotating lever just forward of the film-advance knob (or crank)
labeled "M.U." in the 9:00 position,
where 12:00 seems to be the normal position.

This control does not appear in any pictures in the manual.
Can anyone identify (a) what this control is and does, and
(b) what model this implies that I have?

Thanks.

MU = Mirror Up

lj