Vivitar 35-70 f2.8-3.8

I saw one of these lenses in a camera shop yesterday, and as it was in mint condition (and it's the same shop where I found my Sigma 24mm Super-wde II and Pentax 50mm f1.4 for £30 each) I took a punt and paid the £20 they were asking for it. I can't find much online about it, and was wondering if anyone knew what the P setting on the aperture ring is for? I thought it would be the same as the A setting on my other manual focus lenses, but it does not seem to be. The lens is strange in that 35mm is with the lens extended and 70mm is at the shorter end. I have not tried it out properly yet, but it seems to meter correctly in Av using the aperture ring to set the aperture. It also claims to be a macro lens, but only goes to 1:6 on the focusing ring, which is nice and chunky.
Does anyone here have one of these lenses, and if so, any info on it?

The 35mm-at-the-long-end is identical to the Pentax-M lens of the same focal range, I was a bit puzzled by it too until I saw the theory that it's intended for stability. When you pull the lens in to 70mm the camera becomes steadier as your hand is closer in.

Many older lenses claim "macro" but really just offer close focusing.

I'm intrigued by it metering correctly in Av using the aperture ring, this shouldn't be possible!

This one? link

It's a Ricoh "PK-AR" mount:

The hazard from the infamous Ricoh "pin" is very real. There are two variants of the "pin". One is a rigid, retractable pin and the other is a spring-loaded ball. Both are located such that they will "fall" into the AF slot drive on the camera body causing the lens to jam on to the mount. The ball type can be fairly easily wiggled out of the AF slot. The pin type is much more difficult.

The lens may be modified and made safe by disassembling the mount to remove the pin.



Read more at: http://www.pentaxforums.com/forums/pentax-slr-lens-discussion/85262-ricoh-p-lens...#ixzz1OCNvbEcl

John

I was a bit surprised it meters in Av using the aperture ring too, and after another fiddle with it it looks like the aperture actually remains wide open whatever I set on the aperture ring. The aperture ring works perfectly off-camera Any ideas?

Yes that's it.

Thanks John, I guess that answers why its not working properly. Whoops. I will try and remove the pin.

Hmmm.....the lens I have does not appear to be either of the problem ones (no ball or thin wire pin). The lens fits fine and the lens mount looks identical to my other manual focus primes, with a rectangular pin. The only problem seems to be the lens stays wide open when mounted on my K7. The mount is R-P/K accorfing to the markings on the lens. Any ideas?

That sounds more normal!

In Av mode the lens is held at the widest aperture regardless of what you set the aperture ring to. To use all the apertures you need to do the stop down metering in M mode trick.

From what I understand the Ricoh pin is only found on PK-A fit lenses intended for their later SLRs, I'd imagine your version of the lens just says "R-P/K" for sales purposes, as it's highly likely that a lot of Ricoh owners were unaware that lenses made to fit the Pentax K mount would work on their camera.

I know that 1985 Argos catalogue scan someone posted a link to a while ago had similar wording around the Hanimex zoom lenses - the K mount was stated to fit the ME Super and the Ricoh they also sold.

Thanks Matt. What's confusing me is the lens looks like the aperture should be able to be controlled by the camera. The aperture control looks identical to my Pentax A 50mm. I am guessing the P setting on the lens is equivalent to the A setting on my other lenses. The mechanism looks identical. I will try it out in M though and sees if it is worth persevering with this lens.

If you look at the lens mount, does it have any of the little studs as on the A series lens? I can't think what else "P" would be for.

It's for use with program modes on Ricoh cameras such as the Ricoh XRX.

See:

http://www.butkus.org/chinon/ricoh.htm

http://forums.steves-digicams.com/pentax-samsung-dslr/64881-one-last-word-ricoh-...

John

Thanks all for the info, especially John. I have returned the lens and got a full refund. Got a 135mm f3.5 for £30 off ebay yesterday so hope that proves more successful!

Which 135mm is it? Pentax-M?

Cracking little lens, there are sharper out there but I don't really think you can beat it for the money.

Yes it's a Pentax M. Seems a nice lens, came in a case and I like the built in hood. Hopefully be trying out out on a new K5 I am hoping to pick up today!

Have you tried the Pentax M 75-150mm zoom? Some say that it's sharper than the 135mm. I bought mine in perfect nick for less than £25.

Andrew