Instrumentation requirements of test programs involving rockets, rocket sleds, and other projectiles are often such that a capability of tracking the projectile with an optical system is highly desirable, both because of the economy of fewer cameras and equipment required for adequate coverage, and because of the more satisfactory data which can be obtained in this manner. Manual tracking of these projectiles is unsatisfactory and often im-practical due to the high accelerations and the fact that the duration of the tests is of the same order of time as the human reflex. Several proposed systems for automatic and programmed tracking utilizing both digital and analog techniques are discussed, and available results of tests of some of these systems are presented.

"It should be emphasized at once that no single number can be attached to any system to describe completely its capability of reproducing detail clearly." Drs. George C. Higgins and Fred H. Perrin "....it has been increasingly realized that the advantages of resolving power as a criterion of quality are illusory. In the first place, it is not a fundamental property of the photographic material...In the second place, the criterion is uncertain...." Dr. Fred H. Perrin 4

The universal airborne camera capsule was developed to obtain the photographic coverage needed for better flight-test documentation. The capsule design and modifications, type of camera equipment, timing device and electrical system are described. The capsule has been test flown at speeds up to Mach 1 without need for excessive trim adjustments. Pilots' comments have favorable, and photographic coverage obtained has been good.

The modern inventory of vacuum coated multi-films is reviewed; uses for ultra violet and infrared applications are shown; technical data and transmission curves are provided.