Dougg
Seasoned Member
Pentax has a long history of emphasizing optical excellence, with Zeiss as their quality target. The Super-Multi-Coated Takumars introduced about 1970 were their best yet, and featured a mechanical f-stop communication with the last of the M42 bodies, the Spotmatic F, ES, and ESII, for open-aperture metering. (They also work fine in the older way on the older stop-down bodies).
After the bayonet-mount came along in 1975, the basic body structure and the lens construction were direct continuations of the previous models. At this point they mostly dropped the "Takumar" lens name, substituting "Pentax", and the body model designations were all "K-"something; K2, KX, KM, and K1000. So these lenses were thought of as "K" mount.
The cameras had become larger and heavier in these years, and maybe spurred on by the little Olympus OM, Pentax began offering more compact models with "M" in the name... ME, MX, etc, and a line of more compact M lenses. While the MX developed a devoted following, and the M lenses were excellent, many users still preferred the "K" lenses as perhaps being more solidly made and more sophisticated optically, without the M compromises for size and weight. These "K" lenses were not marked as such, just SMC Pentax and not SMC Pentax-M, and sell for more in the used market. BTW, any bayonet-mount lens marked "SMC Takumar" like one variety of the 2.5/135mm is a further simplified price-leader.
The KA mount was a later development, I think at the time of the Super Program, adding body control of the lens aperture and an A setting on the aperture ring. And an "F" in the lens designation indicated auto-focus. And here I fade out, not having paid much attention to detail developments since! Our most modern 35mm Pentax is one of my wife's remaining battered LX bodies, the other gone missing, and it needs to be sent to Pentax in hopes it can be refurbished. I use a K2DMD, an MX, an ES and ESII, a Spotmatic Motor, an H3, and a 1958 model K with its slow-speed shutter dial separately mounted on the front as with a classic Leica or Canon RF.
All their lenses have a little rattle when shaken, surely due to the auto-diaphragm parts not being under tension with the lens off the camera, and I recall this same question also coming up about the big 6x7 Pentax lenses at Photo.net...
After the bayonet-mount came along in 1975, the basic body structure and the lens construction were direct continuations of the previous models. At this point they mostly dropped the "Takumar" lens name, substituting "Pentax", and the body model designations were all "K-"something; K2, KX, KM, and K1000. So these lenses were thought of as "K" mount.
The cameras had become larger and heavier in these years, and maybe spurred on by the little Olympus OM, Pentax began offering more compact models with "M" in the name... ME, MX, etc, and a line of more compact M lenses. While the MX developed a devoted following, and the M lenses were excellent, many users still preferred the "K" lenses as perhaps being more solidly made and more sophisticated optically, without the M compromises for size and weight. These "K" lenses were not marked as such, just SMC Pentax and not SMC Pentax-M, and sell for more in the used market. BTW, any bayonet-mount lens marked "SMC Takumar" like one variety of the 2.5/135mm is a further simplified price-leader.
The KA mount was a later development, I think at the time of the Super Program, adding body control of the lens aperture and an A setting on the aperture ring. And an "F" in the lens designation indicated auto-focus. And here I fade out, not having paid much attention to detail developments since! Our most modern 35mm Pentax is one of my wife's remaining battered LX bodies, the other gone missing, and it needs to be sent to Pentax in hopes it can be refurbished. I use a K2DMD, an MX, an ES and ESII, a Spotmatic Motor, an H3, and a 1958 model K with its slow-speed shutter dial separately mounted on the front as with a classic Leica or Canon RF.
All their lenses have a little rattle when shaken, surely due to the auto-diaphragm parts not being under tension with the lens off the camera, and I recall this same question also coming up about the big 6x7 Pentax lenses at Photo.net...
