Why is the calf thicker than the thigh in the shadow?

The fact that the calf is thicker than the thigh in the shadow is influenced by the angle of light irradiation. Different angles of illumination will make a great difference in the thickness of shadow legs, similar to taking pictures in front of a mirror. It is not accurate to simply believe in the thickness of the legs in the mirror. If you want to know the thickness of the calf and thigh, you need to put the phone into the self-timer function and find a suitable angle to judge.