The analysis of many high explosives (HE) involves the use of rotating-mirror cameras and high speed film. Fiducial timing spots are made on the film to provide temporal reference to the experimenter during subsequent evaluation. The writing speed of the 'streak' camera is 10 millimeters per microsecond, thus, the optical fiducial pulse width must be on the order of tens of nanoseconds to generate a useful spot size. For this application, a useful spot size corresponds to a width of 200 to 300 micrometers. Present systems employ light-emitting diodes for this task, mounting them at the focal point of the camera. However, the size and clarity of the current timing spot on the film is less than optimum. Furthermore, experiments involving high explosives require the isolation of the electronic instrumentation from the experimental hardware and passive operation is always preferred if not required. This is due to safety requirements as well as instrumentation ground loop and EMP concerns. Another restriction is the diminished sensitivity of the high-speed film to wavelengths above 600 nanometers, which narrows the field of possible optical sources considerably. A passive, fiber-coupled system based upon a 635 nanometer laser diode has been developed and tested. The development process, final design and test results are presented and the improved signal resolution is compared with current technology.