Making a better shutter

This paper will describe the development of better shutters for astronomy instrumentation at the CFHT observatory. Over a six year period several exposure control shutters and shutter like devices have been built by modifying existing products or custom machining in house. With each new shutter project, experience from the previous shutter design enhances development. This has resulted in the latest shutter, a magnetic latching, springless, low power, sensed exposure shutter to be used for CFHTIR, an IR camera.