2 A B C D E F G H I K L M N O P R S T U V W
Ra Re


A normal lens has pincushion distortion or barrel distortion which can be corrected to give a perfect perspective projection, like the image of a pin-hole camera.
This process is called “rectification” and is often applied for stitchich images, for example, in panoramic photography.
The resulting images has no distortion.