It applied the method of on-the-spotphotograph to comparing the stroke frequency and rhythm of the male and female kayakers who took part in the "World Cup".
采用现场摄影法，比较世界杯赛中男女皮艇运动员的桨频和划桨节奏。
2
Go back to the same spot every couple of days to watch and photograph the same plants as they develops.
每隔几天回到同一地点拍照同一棵植物，以记录它的生长，直到花开。
3
For aerial photograph pair, the Orthophotomap of the image - overlapped region can be made by calculating directly spot height at image point.