Definition of perspective deformation

We have seen close-up portraits taken with wide-angle lenses, and the nose of the subject will appear surprisingly large compared with other facial organs. This is a feature of perspective distortion in many photos taken with wide-angle lenses.

As the picture shows, the dog's nose is a typical example of this perspective deformation.

In order to understand the original intention of this distortion, let's first discuss the normal perspective. As we all know, one way for our eyes to feel the distance is to use the relative size of the object, and the brain will tell us that the farther away the object is, the smaller it is.

In photography, the perspective relationship is also identified in the same way. Objects in the distance are smaller than those of the same size nearby. For this reason, when we look far away, parallel trajectories will get closer and closer until they converge.

Another manifestation of perspective is that the closer the object is, the stronger the perspective effect is. For example, 200 soldiers marched in a single file. If you watch or photograph the parade at a distance of 10 feet from the soldier in front, the soldier in front will appear much taller than the last soldier. However, if you watch or photograph the same team at a distance of 100 meters from the soldier in front, the size difference between the first soldier and the last soldier will not be so big.

These two features of perspective also apply to all shots, namely:

1. The farther the subject is, the smaller it appears;

2. The farther the lens is from the subject, the smaller the appearance change of the subject.