Pentax 135mm Lens

Did Pentax ever produce an 'A' version of this lens? Also can someone explain the difference between Pentax-M and Pentax-K Bayonet fitting.

SMC Pentax K lenses, only marked SMC Pentax by the way, were the original bayonet lenses introduced with the KM, KX and K2 cameras in 1975. They were basically bayonet versions of the final SMC Takumar screw thread lenses.

SMC Pentax-M lenses (and marked as such) were introduced with the compact ME and MX SLRs and are suitably compact to take advantage of the size reduction. These are largely new designs although some are the same optically as the previous series.

There have been quite a few 135mm lenses, including SMC Pentax-A versions. Whereas the K and M lenses have the plain bayonet mount, the A series introduced the electronic contacts that are still with us today.

Thanks John. When you say the M lens are compact does that mean the bayonet is different or the lens is compact but on the same bayonet fitting?

The lens is compact. The bayonet stayed the same and all lenses from Pentax are compatible, in terms of fitting anyway.

Barrie, you might find this site useful:

http://stans-photography.info/

However, it is not error-free. In particular, there is confusion between the SMC Pentax 1:2.5 135mm and the Takumar (Bayonet) 1:2.5 135mm. The latter, known in America as the "Bow-wow Takumar", is uncoated but otherwise not too bad.

G

I've been looking on EBay and there seems to be a number of versions for this lens. Any recommendations on which to look for and which to avoid?

Look at the site I just linked to.

G

They really are ignoring you today George

Precis:
The A* 1.8 is great, but rare and expensive.
Same, to a lesser degree, for the SMC K 2.5.
The A 2.8 is rubbish.
The M or K 135 3.5s are good.
If I were you I would seek an F or FA.

G

A rare treat!

G

Who could ignore George, that would be rude. Unfortunately I replied to John’s post without refreshing my screen, so had not seen the last one.

I have the A 2.8 version, and don't really recommend it. You have to work hard to get good results - it can be lacking contrast in particular. I found it to be a reasonably good lens for stage events, where you can't get physically quite close enough to the action, and where the background is dark. IMHO the lens is sharp enough, however, and is easy to focus.

Are you trying to cause bother George

I had the M 135mm f3.5 it was a superb bit of glass, had some nice shots from it with my MZ7 and 5n, unfortunately I sold it after buying my istD as I felt it wasn't compatable enough.

Moi?

Seriously, the A 1:2.8 has few friends, whilst the M and K 1:3.5 are held in quite high regard, by you and many others.

G

Yes, agreed. I wouldn't buy another A 2.8.