In air photography, what term refers to the point where the optical axis intersects the ground?

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Multiple Choice

In air photography, what term refers to the point where the optical axis intersects the ground?

The central idea is the reference point defined by the camera’s optical axis. This axis meets the image plane at a single spot, the principal point, which serves as the origin for image coordinates. When relating the photo to the ground, that same axis marks a specific ground point directly beneath the camera, giving a consistent reference for plotting, measuring distances, and orienting stereo work. That fixed reference on the image (and its ground counterpart) is called the principal points.

The central idea is the reference point defined by the camera’s optical axis. This axis meets the image plane at a single spot, the principal point, which serves as the origin for image coordinates. When relating the photo to the ground, that same axis marks a specific ground point directly beneath the camera, giving a consistent reference for plotting, measuring distances, and orienting stereo work. That fixed reference on the image (and its ground counterpart) is called the principal points.

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