[bassek]

Wow- thank you so much for much responses- the exact name is :

PENTAX 28MM F/2 SMC M K MOUNT MANUAL FOCUS LENS

OK, that lens SMC Pentax-M 28mm F2 Reviews - M Prime Lenses - Pentax Lens Reviews & Lens Database is not the same as the K-series 28/2 SMC Pentax 28mm F2 Reviews - K Prime Lenses - Pentax Lens Reviews & Lens Database .

The M-series goes for half the price of the K-series (was it a Zeiss clone?) one.

Seb

[gofour3]

The M-series goes for half the price of the K-series (was it a Zeiss clone?) one.

The K28/2 was a joint development between Asahi Pentax and Zeiss and was not a clone. Both companies released their own version of the same 28/2 lens in 1976.

Phil.

[mano]

If in doubt whether it's the K or M, the lens' size is a good clue. The K28 2.0 looks more like a 100+mm!

[KatPal]

Yep, it seems all too confusing...could not they make it simpler and release only one :-)

[sterretje]

Yep, it seems all too confusing...could not they make it simpler and release only one :-)

It says M in the description that you posted earlier. Not sure what is confusing about that

Two quotes from another thread (from 2010)

In layman's terms:

M42: first kinds of lenses Pentax produced, for old screwmount bodies such as the Spotmatic; they can be adapted to all K-mount cameras

K: first bayonet series, no actual "K" markings

M: second bayonet series, some say the "M" marking stands for "mini" as most comparable lenses are smaller than their K counterparts

A: in general, K- or M-series lenses updated with auto-aperture contacts, and sometimes worse build quality

F: first foray into AF lenses

FA: second foray, mostly just physical re-designs of F lenses, but also some new ones (I think)

DA: third line of AF lenses, usually deigned for APS-C sized sensors only (but NOT always)

*: higher build or optics quality for older lenses (before Limiteds were introduced)

Ltd.: Limited lens, arguably the highest-build-quality among lenses Pentax has made, very compact lenses for their focal length, and highly superior image quality to comparable lenses

the real difference between K and M is that the M series attempted to retain most lenses with a 49mm filter, and be very compact. The idea was to keep 49mm filters as a standard to help the photographer in reducing the number of filters. WHile this did not impact some lenses, others disappeared or changed.

in the M series, there was no 50mm F1.2, the 85mm went from F1.8 to F2, the 135mm F2.5 was dropped, the 200mm F2.5 I think got dropped and only a 200mm F4.

Additionally I think many of the wide angle lenses went to F3.5 as opposed to F2 or F2.8, but I am not really sure.

There were some improvements, however, specifically in the 300F4 which was downsized a little, and the 400F5.6 which became auto aperture as opposed to preset.

While some people consider the K mounts as re-packaged SMC Taks some were much better optically.

[npc]

M version sells for around $250 , the K for $700-800 lately.
Both are of more interest to collectors than for real use, especially on asp-c

[sterretje]

Both are of more interest to collectors than for real use, especially on asp-c

I can very well imagine that they are very useful if you're looking for something with an equivalent 'more or less normal' view; for me definitely more useful than a 35mm.

[mannyquinto]

I have both the K 28mm f2 and a DA 21 HD. For touring, autofocus has its advantages and I would recommend the HD version of the DA 21. The K 28mm F2 is a rare collectors lens and has a beautiful rendering - it was made w/ collaboration with Zeiss. If you like manual lenses, you will love this lens. You can also consider the K 28mm f3.5 which is much cheaper and also has a good following.