Seconds pendulum
Strobist: 1 tungsten bulb right of and behind camera. I SB800 flash behind subject, camera left set at 1/128 in stroboscopic mode for 20 flashes at 20hz, triggered by PC cord to camera. Second SB800 flash behind subject camera right also set at 1/128 power fired by built in slave. Pendulum was set up to have a period of approximately 2 seconds; each swing took about 1 second (A seconds pendulum.) 1 second shutter speed. I tripped the shutter as the pendulum reached its farthest leftward movement.
Seconds pendulum
Strobist: 1 tungsten bulb right of and behind camera. I SB800 flash behind subject, camera left set at 1/128 in stroboscopic mode for 20 flashes at 20hz, triggered by PC cord to camera. Second SB800 flash behind subject camera right also set at 1/128 power fired by built in slave. Pendulum was set up to have a period of approximately 2 seconds; each swing took about 1 second (A seconds pendulum.) 1 second shutter speed. I tripped the shutter as the pendulum reached its farthest leftward movement.