Posts: 791
From: Northridge, CA USA
Registered: Jun 2003
posted November 26, 2005 04:14 PM
I actually have a Bell & Howell reg8/super8 projector with a four blade shutter, but I made the shutter and replaced it in the projector. I chose that model because at the time it was one I could get the old shutter out of easily.
Making one isn't really difficult. Remove your three blade shutter and use it as a guide for the proper diameter and draw one blade--the prime blade. That's the blade that covers the aperture during the pull down. Now duplicate that blade on your drawing opposite and then replicate those two blades at 90 degrees and you have a four blade shutter drawing. Transfer it to sheet aluminum and cut it out. Paint it black with high temp stove paint and then install it in the projector making sure that the prime blade is timed properly to the pull down.
Your four interruptions (as you know) will give you proper flash rate for 15 fps for telecine in the US. A three blade shutter will allow you to operate at 20 fps. 15 is close to 16 for old 8mm silent home movies and 20 is close to 18 for Super8 home movie.
Posts: 264
From: Fairfield, OH, USA
Registered: Feb 2004
posted November 27, 2005 10:58 PM
I did this exact same thing about 4 years ago on a Bell and Howell R-8mm projector and added a sync motor drive to it. Works great for telecine transfer of R-8mm film shot at 16fps. Lots of B+H projectors lend themselves to this type of mods.