What kind of distortion is included in image photography? List and explain.

Photography is inseparable from optical lenses.

The lens consists of an optical lens group.

When light passes through the lens, it will distort the image.

That is, there is a slight difference between the physical object and the photo imaging, and this difference is always called aberration.

Among them, aberration can be divided into single aberration and chromatic aberration.

Subdivision can be divided into spherical aberration, coma, curvature and astigmatism, distortion, chromatic aberration and so on.

The lens distortion is obvious and easy to understand.

Distortion is actually the general term for the inherent perspective distortion of optical lenses.

Which is the distortion caused by perspective.

This distortion is very unfavorable to the imaging quality of photos. After all, the purpose of photography is reproduction, not exaggeration.

But because this is the inherent characteristic of lens (convex lens condensing and concave lens diverging), it can't be eliminated and can only be improved.

The optical design and materials of high-grade lenses are exquisite. Using the optimized design of lens group and selecting high-quality optical glass (such as fluorite glass) to make lenses can reduce the perspective deformation to a very low level.

However, it is impossible to completely eliminate the distortion. At present, the best quality lenses are tested under extremely strict conditions, and the edges of the lenses will be deformed and distorted to varying degrees.

Spherical aberration and coma are also one of the characteristics of lenses, which cannot be eliminated fundamentally and can only be reduced as much as possible.

With the current optical technology, these aberrations are difficult to feel in the center of the picture.

But at the edge of the picture, even at the edge of the advanced lens, experienced film friends can still feel it.

This problem involves too many concepts and is too complicated.

Say it in general.

In fact, every kind of distortion can be described in detail.

Time is limited, so let's call it a day.

If you want to know more, it should be easy to find relevant information on the Internet.

Please ask questions in detail if you have any questions.