The Time Telescope

Abstract

The “time telescope” or combination time-lapse and photoelectric exposure control machine speeds up imperceptible motion. The variable-exposure control with exposure modulator gives either a gradual change in density, or equal average frame densities regardless of spectral or intensity changes in subject lighting. It corrects for failure of film to follow the reciprocity law. Photoelectrically regulated, it automatically exposes the subject properly regardless of changes in color, area, and average light intensity during or between exposures. Long periods of time between exposures make possible the use of a small fixed diaphragm (f/256).