Pentax ME super question

Cheers for the extra links, any others that explain the differences in the K M and A series lenses?

K lenses are marked SMC Pentax and were the original bayonet series.

M lenses are marked SMC Pentax-M and are the compact lenses produced to complement the MX and ME series cameras

A lenses are marked SMC Pentax-A and were produced for the A series cameras and these have electrical contacts on the mount, which makes this the Ka mount. These lenses and later will work fully with the digital SLRs. They are further identified by having an "A" setting on the aperture ring.

The K and M lenses have no electrical contacts and this restricts the way they are used on DSLRs. But they can be used.

So called K series lenses are the original K mount lenses which arrived with the K1000 and friends in the mid 70's. Mechanical only, generally optically good for their time.

M series lenses get an M suffix on their name, eg Pentax SMC-M 28mm F2.8. These came along a little later to coincide with the M series of cameras, ie MX, ME, MV, MG, ME-Super etc. They are still fully mechanical with no electrical contacts at all. They are generally smaller and lighter than K series lenses (although one or two are just re-badges of the K series versions). Optical quality again is generally very good for their age. A few are not quite as optically good as the K series, having suffered from the efforts to make them small and light. For example, the K series 200mm F4 is said to be slightly better than the M 200mm F4.

A series lenses match up to the A series and P series cameras. These are the last non AF Pentax lenses. They gain electrical contacts which allow matrix metering, shutter priority and program modes. Crucially for us, the contacts allow aperture control from the camera body, making the A series fully usable on Pentax DSLRs.

Edit: oops, John types faster than I do!

Thanks chaps, that clears that up.