Photography has a Sam rule. What do you know about it?

Also known as Sham's law, it is transliteration, which is actually a principle of angle adjustment when shooting. Mainly used for large format cameras, such as Shana, Lin Hafu, Knight, Constellation, Jinbao, Shen Hao, etc. Or some lenses with adjustable angle of view, such as Canon, Hasselblad, Mamiya and other brands all produce lenses for this special purpose. The lens of the camera we usually use does not have this function, but the lens with adjustable angle of view can have a certain tilt angle between the front and rear lens groups, resulting in perspective deformation. The direct effect can be to adjust the effect of, for example, the near big and the far small to one side, which is very important in architectural photography and advertising photography. Now we always think that post-processing can be done by computer, but that is at the expense of image quality. Indeed, it would be much easier to understand if there were illustrations. I suggest you go to a bigger bookstore or library to consult books about large-format cameras, which will be introduced in detail. If you are just a photographer or don't plan to use this camera in the future, this law has no effect on you.