Pentax lens mount;

The chronological order should be: M42-K-M-A-F-FA.

It is said that K has more materials, more metal components and is heavier than M. But the difference is not very big.

After A (including A), there will be electronic contacts and the fuselage to transmit information.

K(smc pentax)

-The lens marked smc PENTAX is called K lens. K-lens is the first lens group to use the K-lens interface. It is a lens listed together with the release of K series bodies such as K2, KM and KX listed in 1974. Most of these lenses are changed from spiral interface products to K interface. K lens is a manual lens, and the lens itself adopts manual exposure and aperture priority automatic exposure. K lens has been hard to find in the market since M series lens went on the market. However, both optical performance and product integrity have been better evaluated than M lens.

M(smc PENTAX-M)

-It's a lens marked SMC Pentax-M. The M lens is a product released by 1976 together with M series bodies such as MX, ME Super and MV, which is smaller and lighter than the K lens. Like the K lens, it supports manual exposure and aperture priority automatic exposure. Example) SMC M 50mm F 1.4

(smc Pentax -A)

-A lens is a product released in 1983 with super A, programe A and other A series bodies. A contact is added to the lens interface, which can support shutter priority and program automatic exposure in addition to manual exposure and aperture priority automatic exposure. A lens is similar to M lens in weight and size, but some lenses are different from M lens in optical structure. Example) SMC A 50mm mm F 1.4

F(smc pentax -F)

-F lens is a product released together with SF series fuselage of 1986, which adopts AF function. Like a lens, it supports manual exposure, aperture priority, shutter priority, program automation and so on.

FA(smc pentax -FA)

-Although the above M, A and F lenses are extinct models, they are interchangeable lenses with K interface, so I will introduce them to you. FA lens is a product released together with Z-series fuselage of 199 1 year, and F lens has added zoom function and MTF exposure function. In the early days, most FA lenses used power zoom, but because it was judged to be impractical, it no longer has this function in the new FA lenses. MTF exposure function is the function of automatically setting the best performance aperture value for the lens through the MTF curve of the lens.

Tatar is the latest bayonet.

Smc is Pentax's super multilayer coating.