What is a macro lens and how is it different from a normal lens?

1. The main difference between a normal lens and a macro lens is the magnification. The magnification of macro lens is 1: 1, and that of ordinary lens is about 1:3~6.8.

2. The so-called magnification is the size of the image theme on the image sensor. The theme size of the image shot by the macro lens is the same as the real thing, while the theme size of the image shot by the ordinary lens is only 0. 15~0.33 (see figure for the macro lens).

Canon EF 100mm f/2.8L is USM.