Time-Marking High-Speed Film in Multiple-Camera Installations

摘要

The general time-event correlation problem for high-speed (10,000-frames/second), motion analysis cameras is discussed. The specific optics, sensitometry, and electronics problems involved in placing precise time and event marks on high-speed film, in addition to the design and development of an operational time and event signal generator, are discussed. The generator features a tuning fork time standard, integrated circuit timing logic that can furnish independent time and event signals for up to 15 cameras. A current ramp-film density wedge generator is presented as a novel method for relating time-mark lamp current amplitude to film-mark density. Recently developed, solid-state, light emitting diodes (LED) were investigated for application to the time-mark problem. The LED proved capable of providing time-marking pulses at rates in excess of 200 kHz. A technique for analyzing a waveform to operationally test the neon lamp timing circuit is evaluated. (Author)