Classification of UAV aerial survey by distance belongs to what kind of photogrammetry?

1, according to the tilt angle of the photo (the tilt angle of the photo is the angle formed by the main optical axis of the aerial camera and the ground vertical line (the main vertical line) passing through the lens center), it can be divided into vertical photography and oblique photography.

2, when the tilt angle is equal to 0, for vertical photography. At this time, the main optical axis is perpendicular to the ground (coincident with the main vertical line), and the photosensitive film is parallel to the ground. However, due to various reasons in flight, the inclination angle cannot be completely equal to 0. Generally speaking, any tilt angle less than 3 is called vertical photography. A photograph obtained by vertical photography is called a horizontal photograph. Generally speaking, the image of the ground object on the horizontal photo is basically similar to the shape of the top of the ground object, and the proportion of each part of the photo is also roughly the same. Transverse photos can be used to judge the position relationship of each target and measure the distance.

3. If the tilt angle is greater than 3, it is called tilt photography, and the obtained photos are called tilt photos. This photo can be used alone or in combination with a horizontal photo.