SMC 135 f2.8

I found and bought one of these (second-hand obviously!) in one of our local camera shops. It's got the A position on the aperture ring, so far I'm happy with it.

It has a built-in metal hood that slides out the front, and doesn't rotate when focussing (good when using a polarising filter).

The focussing is fantastic - smooth and accurate, having a very long 'travel' - the downside is that quick focussing isn't so easy.

Anyone else have one or seen one of these? Any experience or comments? I'd never seen one before.

I have the FA version which I bought from another forum member who defected to 'the dark side'. It's an astonishingly sharp optic.

Mine says Pentax-A, so I assume it's not FA.

(Edit - I can't type today - migraine)

Pentax-A was the last, and arguably the best, of the manual focus series of lenses. F, FA, FA-J, DA, & D-FA, all auto focus lenses, have followed since.

The Pentax-A series lenses are certainly more compatible with the DSLR's than the older K & M series lenses as long as you leave it on the A setting on the aperture ring and set the aperture on the body.

http://www.bdimitrov.de/kmp/lenses/primes/tele/A135f2.8.html

With its simple 4-element formular, this lens wasn't one of the best in the A series according to the comments at

http://tinyurl.com/cyxhbe or http://www.stans-photography.info/LongComments.html#50%20mm%20Lenses

The earlier K version is arguably better, though it is heavier and less convenient to use with digital cameras:

http://www.bdimitrov.de/kmp/lenses/primes/tele/K135f2.5.html

I wouldn't take to much notice of comments on that particular site. A lot of them are absolute nonsense. e.g. Take the first review:

"It was replaced by the F135/2.8 in 1989, which is the same
optically as the FA135/2.8 which I own and love."

The F lens came out in 1987 and the A lens was made up to 1989... weird way of replacing it especially with a lens that would be difficult to use on an A body. The FA135/2.8 which he/she owns and loves was trashed by another reviewer lower down.

"The latter has 0.7 meters min distance, as compared
to the 1.2m for the A-model. I think the M135/3.5 is
far better, though slower."

Keh!!! Because it won't focus to 0.7m and only manages 1.2m a lens that focuses to 1.5m is better than it?

They seem to rubbish 4 element lenses on that site quite a lot..... don't they know that one of the best 135mm lenses ever made was only 4 elements...... Carl Zeiss Jena Sonnar 3.5/135 link


shim

There's nothing wrong with a 135mm f2.8 being 4 elements. A good design will give excellent results. Some of the F3.5 Pentax designs were 5 elements, but were redesigned to 4, so Asahi must have been happy with the performance. Fewer elements does mean higher contrast, even with multi-coating.

The best of the 100-200mm telephotos though is reputed to be the 150mm, which is reported as having superb resolition and contrast from wide open all the way through the range. In this instance the aperture has no effect on quality, only on DOF. High praise indeed. (Source: Kevin MacDonnell)

I didn't know that fewer elements makes for higher contrast - thanks for that - I suppose if I'd thought about it...

Ok, some of those comments on the site are rubbish, but there is also one from Yoshihiko Takinami - who does seem to know what he's talking about, judging from his numerous other comments there on other lenses he tested:

"As for the optical performance, K135/3.5 is far sharper wide open than A135/2.8. A135/2.8 is a bit soft."

Yoshihiko Takinami is quite well known and has his own site link
he is one of the better posters to that site (stans)

Strangely the 150mm f/3.5 mentioned by John doesn't come out too good.

I remember seeing a very good and comprehensive test of all available 135's in a magazine in the 80's (sister mag to AP I think) based on proper resolution tests and the Zeiss Jena was the best by a big margin. Some of the runners up weren't major brands either. They also tested all the 28mm's in another issue. 135mm and 28mm being essential buy's at the time.

I never owned a Zeiss but the sharpest 135mm I've ever had (by a big margin and I've still got it) fitted the OM1 and OM2 I had. I'm watching ebay for a Pentax fit one, so I can't tell you the make. It's an f/2.8

shim

I'm not sure that the 150mm lens mentioned wasn't the f4 version, but I'd have to wade through a decade of "Photography" to check.

Hardly worth it John, quite a lot of zooms are actually sharper than 135mm upwards telephotos. I sold my Pentax 200mm when I found that my 80-200 f/4.5 M was sharper than it. If you look at the telephoto tests on that page the highest is 87 whereas the primes go up to 110 with a 50mm macro.

There have been many tests showing zooms reaching almost the 50mm prime standard never mind the telephoto standard.

shim

I have the manual SMC Pentax-M 135mm F3.5 and its very good. One of my sharpest lenses.(The other sharpest lenses I have are the SMC 30mm F2.8 and a Vivitar 200mm F3.5)
bb2

All the medium (100-150) telephotos of the K/M/A are at least very good. I have owned and used the M 100 2.8, the M 120 2.8, the M 135 3.5 and even the non-SMC K 135 2.5 (which does not have so good a reputation - sharp enough but contrast a bit weak) and all gave me good results. My current posession in that range is the A 135 2.8 which I find to be a very nice lens out in the field, great for low DOF shots and seems pretty sharp even wide open. CA seems mnangeable too, though pairing it with a close up lens caused me few problems.

The 200 f4, however, has a fairly modest reputation. I had one but there was no real advantage over a zoom so it rarely got used.

Utterly unscientific, but I have the SMC-K 135mm f/2.5 with which I have been very pleased. It certainly seems sharper and more contrasty than my SMC-M 200mm f/4.