[supablaz]

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I just received this lens from Japan and want to adapt it to my Canon 7D with an M42 to Eos adapter.
But I have a problem, I cannot turn the iris wheel when it's mounted because a little metal piece, used for the auto mode I guess, make the turn impossible.
Do you have same problems with this lens ?
I also own a Tak 85mm 1.9 and don't have this problem.
Could you please tell me what I need to do to use it correctly ?!


Many thanks

Attached Images

 

[gordon_l34]

Hi,
Put it on an M42 Asahi Pentax body or a K mount Pentax body with the relevant adapter!
If this does not work you could offer it to me!
Regards.

[Wild Mark]

I suspect you might get mixed responses here to your question. Destroying pentax (takumar) lenses for Canon conversion is a hotly debated topic.

That aside I urge you to disassemble the lens to remove the offending part without destroying. It takes some effort and patience but is doable. This way you will be able to reverse the alteration.

Cheers

[Adam]

I just received this lens from Japan and want to adapt it to my Canon 7D with an M42 to Eos adapter.
But I have a problem, I cannot turn the iris wheel when it's mounted because a little metal piece, used for the auto mode I guess, make the turn impossible.
Do you have same problems with this lens ?
I also own a Tak 85mm 1.9 and don't have this problem.
Could you please tell me what I need to do to use it correctly ?!


Many thanks

You'd have to find some way to press it down, perhaps by sticking something between it and the lens mount. For some reason, certain lenses had this as a lock feature for when they weren't mounted...

Adam
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[tromboads]

Firstly, that little metal piece is the indexing for the later model Spotmatics! That is how the later model Spotmatics could determine what aperture the lens was set too. Those tabs were only on the later Super-Multi-Coated Takumars and SMC Takumars

Are you sue this is what is stopping you from moving the aperture?

Super Multi Coated Takumers have a (AUTO-MAN) switch on the side which only works freely whilst a little pin is pushed down. No not the aperture pin sticking out of the back but a tiny small pin found on the mounting surface. This pin needs to be depressed or you can not change between the auto and man settings. This is not found on "Super Takumers" but only on the later SMC and Super Multi Coated Takumers. I worry this switch it set to auto and thus moving the aperture indicator freely does nothing, and you have mistaken the metal bar as the aperture control lever?

I only say as much as I'm confused how that metal aperture indicator could be fouling your canon / or the adapter. They barely protrude and if anything, would hit the mirror, but still not get in the way of you selecting your aperture...

Folk have only needed to cut away at M and K, and A mount lens as they lack this auto / man switch. Your Takumar is good because it has the auto / man switch

[Lowell Goudge]

What is stopping the function is the little pin sticking out the other side of the mount. You n d to depress that pin by screwing the lens cap on and changing the position of the auto manual switch on the lens

[Not a Number]

The little pin that everyone is referencing can be seen on the left hand side of the photo next to the screw threads. Ordinarily this get depressed when the lens is fully screwed into the camera body, accessory (extension tube, TC, bellows). The adapter ring may be preventing this if it has a flange to push in the longer auto aperture (seen at the top of the photo). I would try a different adapter without the flange. You can use the auto/man. switch to stop down the lens without the flange. Save the flanged adapter for lenses without the switch.

Post some photos from various angles of the adapter if you could.

[.a.t.]

. . .
Could you please tell me what I need to do to use it correctly ?!

. . .
I would try a different adapter without the flange. You can use the auto/man. switch to stop down the lens without the flange. Save the flanged adapter for lenses without the switch...

I believe Not a Number is correct.
supablaz, you don't need to modify the lens, just find an M42 to EOS adapter without a flange.

Adapters with a flange depress the (raised) stop down pin, but they also rub against the indexing tab which prevents the aperture ring from rotating. A flange-less adapter doesn't depress the (raised) stop down pin, but it will depress the smaller pin (at the base of the mount) allowing use of the Auto / Manual switch to stop down.

I own both types of adapters. Here are some pictures (the lens is my Super-Multi-Coated Takumar 135 f2.5):

[tromboads]

Well that solves that. no flange wins. You don not need to destroy that lens after all.

REJOICE!

[supablaz]

I want to thank u all for your quick answers !

So, as .a.t. said, I just need a new adapter ! Problem solve ;-)

Many many thanks

Peace

[Big-jean]

Hey I have a takumar 135mm 2.5 but having hard time finding an adapter for it I see your non flange answer but being it's not a screw mount how does it work on this mount? It's to an t6i canon

[.a.t.]

Hey I have a takumar 135mm 2.5 but having hard time finding an adapter for it I see your non flange answer but being it's not a screw mount how does it work on this mount? It's to an t6i canon

Welcome, Big-jean.

You have a Takumar bayonet lens which has a K mount. To fit it on your t6i, you'll need an adapter such as this one:
Fotodiox Lens Adapter Pentax K (PK) Lens to Canon EOS EF-s Cameras Only 847372017591 | eBay

I ordered my PK to Canon adapter from a Chinese seller and it cost less than the Fotodiox, but it took a couple weeks to get here (U.S.). My adapter works fine, but the Fotodiox would probably be better quality.

Here's a link to some info about Takumar bayonet lenses:
Non-SMC Pentax Prime Lenses - Reviews and Specifications - SLR and Interchangeable Lenses - Pentax Lens Reviews & Lens Database

And if you'd like to read more about Pentax mounts, here are some links:
Photos of K and M42 mount variations (photos of pentax k-mounts) - PentaxForums.com
The Evolution of the Pentax K-mount - Articles and Tips | PentaxForums.com