What lens is good for portrait photography?

Canon EF 85/ 1.2L II USM, Leica apo-summicron-m90mf2asph, CZ Planar T* 85mm F 1.2 and pentax FA 77mm F 1.8 Limited are the most representative 135 camera portrait lenses.

A standard portrait lens generally refers to a lens that takes a person at a distance of 1.5m-2m, that is, a lens of 70mm- 135mm.

Portrait photography, you can shoot wide angle, head, middle focus, telephoto and even fisheye, depending on what kind of effect you want. According to the general aesthetic point of view, it is the most beautiful to see a person's five senses from 1.5 to 2 meters away-because the perspective effect of this distance makes a person's nose look slightly smaller than it really is, and his face is not peaceful. Moreover, when taking pictures of people, it is customary to only take pictures of people's heads and shoulders. So what we call a standard portrait lens generally refers to shooting a person's lens at a distance of 1.5m-2m, that is, a lens of 70mm- 135mm. The longer one is ok, but it is difficult to communicate with the person being photographed because of the long distance. As the distance approaches, the deformation occurs again.

A good shot is one that is easy to communicate with the subject without obvious deformation. For the 1 portrait lens 35 camera, the 70mm- 135mm lens is considered as a portrait lens. For APS-C camera, because the image field obtained by the same lens is smaller than that of 135 camera, the lens of 135 camera with a focal length of 50mm-90mm is the portrait lens of APS-C camera. What if it is a child? It stands to reason that we should use a lens with a larger focal length (larger magnification) than the ordinary portrait lens, so that children's heads and shoulders can fill the whole image field. However, because children's facial features are not as prominent as those of adults, they can shoot at a closer distance without affecting their beauty, so it is enough to shoot at a distance of 1 m with the ordinary portrait lens.