Post by Scott DorseyIt might also be possible to take a 16mm pin-registered claw movement,
remove the claw, and add a microprocessor-controlled stepper motor
driving an intermittent sprocket. The stepper positioning does not have
to be perfect because the pin does that job for you.
Assuming you started out with a Mitchell 16mm movement (I'll get into
the specifics later), you would enlarge the aperture above the present
aperture, retaining the location of the "big pin" as the reference for
the new aperture and the old movement.
Now, Mitchell's 16mm standard movement [ * ] is 2R and is good to 128
fps, whereas Mitchell's 16mm sound movement [ ** ] is 1R and is good to
32 fps.
If you double-cycled the movement, but single-cycled the shutter,
thereby getting 2 perfs per shutter cycle, you would be limited to 64
fps for a standard movement, but only 16 fps for a sound movement.
Essentially, whenever you ran 24 fps, in "new money", the movement
would really be running at 48 fps, in "old money".
At 48 fps, you really do need two pulldown claws, which the standard
movement has, but the sound movement does not, and you also need the
"big pin"/"little pin" registration scheme which the standard movement
has, but the sound movement does not.
The sound movement appears to have two registration pins, but the
outside pin is a dummy pin, used only to guide the entire registration
pin assembly. This pin does not project into the film at all, it just
clears it.
The sound movement guides the outside edge of film at the top of the
movement. This is isn't as good a system as the standard movement, but
it works well as the movement components are all hand fitted, and the
movement is limited in its speed.
So, I think you do have some hope, provided you are satisfied with 2R
film, and with a Mitchell standard movement as a start.
[ * ] "Standard movement", meaning Mitchell's 2R high-speed movement,
intended for sound shooting when housed in a blimp, but not otherwise.
This movement is found on the rackover-type Mitchell 16s.
[ ** ] "Sound movement", meaning Mitchell's 1R adjustable pitch
movement, intended for sound shooting without a blimp. This movement is
found on the reflex-type Mitchell 16s, both double-system and
single-system.
--
CinemaScope®: The Modern Miracle You See without Special Glasses!