Solution:Horizontal aerial photographs are also called terrestrial aerial photographs. To take horizontal or surface (terrestrial) aerial photographs, the camera axis is aligned with the horizontal plane. These provide only an elevation view. Horizontal photographs can also be taken with a good camera and are used as a supplement to the analysis of vertical photographs.
They are also of special importance in field studies. They are especially needed for profiles in geological, forestry, and geomorphological studies. To take oblique photographs, the camera axis in the aircraft is tilted towards the ground. These photographs show side views of surface details. Photographs taken with the axis of the aerial camera tilted are called oblique photographs.
These photographs cover a large area on the ground, but the accuracy and clarity of details decrease as one moves away from the center. The use of oblique photography is crucial from a strategic perspective. Therefore, during wartime, these aerial photographs are extremely useful for detecting tanks, vehicles, logistics stores, and armories hidden by the enemy under trees.
Trimetrogen means tripartite, meaning three-dimensional. Three cameras are used simultaneously in a camera unit. The central camera takes vertical images of the ground, while the side cameras take oblique aerial photographs up to the horizon. Thus, in the tripartite system, the entire area from the right horizon to the left horizon is captured.