This me back in the olden days (1977 or so) - I'm sure I was wearing bellbottoms at that time.

I've enlarged the teeny Instamatic photo quite a bit to make things visible.

I'll describe this busy pic. There is a S&W CO2 pellet pistol held in a small clamp-on vise. A Speed Graphic (with Polaroid back) is hanging underneath a tripod, and I'm holding a small Honeywell flash getting ready for the shot. The smaller the flash tube the quicker the quenching -hence shorter duration.

The light will be turned off and the camera shutter held open. At the shot, the flash will be triggered either by mechanical means or with a sound slave. In this pic I can see alligator clips so it was a mechanic switch. Then the shutter will be closed and the lights turned back on and the photo developed.