Abstract
The purpose of this report was to develop guidelines for the operational traffic engineer and the transportation researcher to determine when, where and how to use time-lapse photography. This technique permits the large scale sampling of specific events where the level of detail required, the costinvolved, the elimination of data bias due to the presence or interpretations of field data collectors, negates the use of observers or mechanical/electrical devices. Recommendations are made for data collection, data reduction and record keeping associated with both efforts. (Author/publisher)