(4) It allows observation of movement.
b. It has four major disadvantages:
(1) No permanent record for future direct comparison.
(2) Weather and time of day may limit it.
(3) The observer's experience and mission may limit the information
(4) Human error may result in incomplete and incorrect information.
4. In indirect observation the IA analyzes imagery of the subject, and not
electro-optical (E-C) imagery are used in indirect observation.
a. Advantages of indirect observation.
(1) Comparative cover is successive imagery of the same area which may
detect changes that have taken place.
(2) It results in a permanent record.
(3) It increases the spectrum for
spectrums invisible to the human eye.
(4) It can be distributed to all echelons for their particular needs.
(5) Photographs may be studied at length.
(6) It reduces distance of observation by enlargement.
(7) Radar will usually detect a metallic object behind a
nonmetallic screen, such as a conventional burlap garnished camouflage net.
b. Disadvantages of indirect observation.
(1) The time
(2) Weather may interfere with aerial photographs.
(3) The skill of the IA may limit information obtained.
place of extreme importance, and in regard to camouflage detection and
inspection, photography has reached a stage where it is