Low-Altitude Photogrammetry and Remote Sensing in UAV for Improving Mapping Accuracy

Table 3

Accuracy before and after regional elevation fitting in different survey areas.

Surveyed area	Before correction		After correction		Number of fitting points	Number of checkpoints	Accuracy improvement multiple
	In the error	Maximum error	In the error	Maximum error
1^st part of the surveyed area	0.294	−0.641	0.210	−0.520	16	48	0.284
2^nd part of the surveyed area	0.554	1.262	0.278	0.612	13	44	0.287