Vertical vs oblique imagery

This article explains the difference between images taken at a vertical angle and images taken at an oblique angle.

Vertical images

Images taken by a camera pointing to the nadir direction. Pointing to the nadir means that the camera axis (in the direction of the lens) is perpendicular to the ground / object.

Oblique images

Images are taken with the camera axis not perpendicular to the ground / object.

Vertical and oblique imagery