In this hybrid live action / multiple exposure technique a sequence of frozen images of the subject are progressively left behind as the subject moves naturally through time and space while the virtual camera moves around the subject. The virtual camera movement reveals the three dimensionality of the frozen images.
This technique is achieved by lighting the scene entirely with high speed photo strobes and controlling the relative timing of Digital Air's camera system's shutters and the strobes.
Because of the high number of multiple exposures this technique is best achieved with a moving subject on a black background (to avoid saturation of the subject and / or the background). If a non-black background is desired in the final shot the effect can be composited with a different background plate as in the example below.
To light the sequence below we used forty Broncolor strobe packs synchronized to our 80 lens Timetrack camera systems. The Timetrack cameras produced 80 timing events per second across 40 lighting channels with two separate exposure events per frame-cycle and as many as 80 exposures per frame over two seconds (two seconds being the time it took to record one 80 frame shot at 40 fps).
photo: Harold Edgerton
EXAMPLE - FLASH TRAIL
Project: Lux shower gel TV commercial
Equipment: Timetrack 80 lens straight and curved cameras Client: Lux Director: Vaughn Arnell Production Company: Pagan Productions (London) Producer: Adam Saward Post Production: Glassworks (London)
This example of the flash trail effect was shot in a studio on a black background. The leading "live" image of the actress was illuminated frame-by-frame by strobes that flashed as one Timetrack shutter at a time opened sequentially across the camera system at 40 fps. The irregular trail images were illuminated by another set of strobes that were timed to go off when multiple shutters on the Timetrack camera were opened between those individual shutter events. The softer more regular underexposed images were created by ambient light that was "always on".
