Pentax and M42 lenses

[Tervueren]

I've got my first ever Pentax a K3 and would like some advice regards M42 adapters, I've purchased several of the unflanged variety and they have a clip screwed to them which I presume is a locking feature, to me it looks like it may cause problems, if anyone who uses these adapters could advise me whether to remove these clips or is it safe to leave them on.
Thanks
John

[tromboads]

no problem. standard Pentax mounts had as much. Welcome. there is a big bad world of M42 out there

[Tervueren]

[tromboads]

if you can keep it our of sight for 6 months, when the questions comes with how long have you had that, you can cheerfully reply with "Ages Honey"

[philslizzy]

M42 adapters can be a pain in the ass. Get an official Pentax one if you can. Flanged adapters are best but only for macro, the thin ones can be variable. I had one stick on my camera body and I bent the special key getting it off. And that was one I'd removed the lock pin from. Using lenses without the lock pin isn't likely to make your lens drop off as its quite a tight fit anyway.

[Lloydy]

http://srb-photographic.co.uk/

http://srb-photographic.co.uk/pentax-k-to-m42-lens-adaptor-6073-p.asp

I get mine from SRB, and I have checked them dimensionally against a genuine Pentax one and they are exactly the same, and they work with the spring left in place.
The cheap ones are often rubbish, the dimensions are way off and that can be the cause of them jamming - as much as the spring which can be too long. If I buy a cheap one at the camera fair or somewhere I take the spring off, and on some used a file to make them fit. I use these then as permanent adapters on some lenses by gluing them on.
For removable adapters I always use one with a spring, a stiff focusing lens will turn the lens off the body without it.

[Tervueren]

Thank you all and Lloydy thanks for the link, I'll get a couple ordered. I have 4 of the cheapies and although they look ok I've been afraid to mount them yet lol, I think I'll remove the clips from these and use them as a permanent fixture on some lenses and keep the ones you recommend for swapping around, now just want the weather to calm down a bit or I'm off to tescos to get some flowers to practise with

[tromboads]

That's anther point, I've known a few folk to *glue* the ring to the M42 lens. and treat them like K-mount forever more.

I'm temped to glue the M42 ring into my K10 however, if only to stop the "wiggle" that some of the larger lens, well lenses that don't sit against the outside lip flush

[hoanpham]

I use several original pentax adapters. Changing lenses might be slower, but they should not give any problem.

Do not glue the adapter and the lens: m42 works better with canon FF than with pentax mount.

[Kamosor]

Buy only original Pentax adapter. The prices of used original Pentax m42 adapters on Ebay are almost the same as new. Mount and dismount it takes 3 sec. You don't need a key.

http://www.bhphotovideo.com/c/product/673977-REG/Pentax_30120_Mount_Adapter_K.html

https://www.youtube.com/watch?v=6U2gRSqLpPM

[dnf_spedition]

I use the Kipon adapter on my Pentax K-x. I removed the black spring because it got stuck in the camera mount. Most M42 lenses fit well. Russian Helios lenses especially the 50 mm like M44-.. will not fit tight enough with the adapter on my Pentax K-x. Regards Cliff.

[Big Dawg]

Get the Pentax brand adapter. It is a thousand times easier and better than all the rest put together.

[DConvert]

Whilst the cheapest third party ones are useless, I've got several that are effectively identical to the Pentax ones, with the spring type retaining clip. Avoid any with a key to remove them or a flange...

I certainly wouldn't glue one into the camera! The spring is SUPPOSED to stick in the camera mount converting the camera to M42. If you only have both PK & M42 lenses this is a pain and it works well to remove the spring and use one adapter for each lens. Use thread lock if you want to fix it so the adapter can be removed if required.

If you want to use these adapted lenses with Canon FF bodies that's easily achievable with a EOS-PK adapter - without the faff of unscrewing every lens change.

[The Barbarian]

I usually take out the spring and use loctite to hold the adapter on the lens. That can be removed later, with some care. I don't trust any of those adapters to not get stuck.

Works fine for me that way. There's sufficient difference between the feel of focusing an old Takumar and the feel of unscrewing one.

[cooltouch]

I bought a Pentax K2 a while back and it had an SMC Tak 55mm f/1.8 attached to it. I thought it was a K-mount lens, until I noticed it didn't have the big white bump where the lens disengagement button is located on the mount. It didn't want to dismount easily, so after some experimentation, I realized it was M42, and just unscrewed it, only to find a genuine Pentax adapter mounted into the lens mount. It didn't want to budge easily. I used a screwdriver wedged into a crevice and was able to back it out of the mount without too much difficulty. But I haven't used it since. It's too much trouble having to dig out a screwdriver every time I want to change a lens.

[DConvert]