How big is the error of aerial photography data?

Theoretically, aerial photography and maps have the same scale. Calculate the actual area multiplied by the scale, with high accuracy. The result of one measurement cannot be guaranteed to be correct, and it needs to be measured many times, but there is still some error between the measured values and the actual area. As for the proportion, it depends on the angle and accuracy of aerial photography.

It depends on the resolution of the camera and the flying height.

The error of aerial data is small, but it depends on many aspects. Aerial photography data is only one or more videos that truly reflect the actual situation, and the error is not big, but the videos are different, involving parameters such as coordinates, and there are still some errors. If you want to measure the area of a piece of land, you must use satellites or satellite positioning, knowing that there is a certain error in actual measurement.