[mccririck]

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I have recently purchased two M42 lenses. The 135mm F3.5 Super Takomar and the 200mm F4 Super Takomar. I also bought an M42 to K-mount adaptor, and just wanted to ask are these safe to use with big heavy lenses? The one I bought is not as wide on the camera lens mount as a normal lens - you can still see the red dot and the screws holding the mount on.

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Last edited by mccririck; 04-17-2019 at 12:10 PM.

[torashi]

Yes, they are safe. Specially if it's the original Asahi/Pentax one. 135/3.5 and 200/4 lenses may be a bit long, but aren't that big or heavy.

[mccririck]

My adaptor is a "Pixco" from ebay.

[marcusBMG]

Check for rough edges etc n 3rd party ones, like I had to with this:

Kipon M42 to PK adapter reviews - Pentax Camera Accessory Review Database

This is a useful read:

M42-PK adapters - some personal experiences

[mccririck]

I've found this one on ebay which is much wider where it meets the camera:

M42 Lens To Pentax PK Mount Adapter Camera Ring For K-500,K-5II,K-5IIs,K-30,K-7 | eBay

[torashi]

I've found this one on ebay which is much wider where it meets the camera:

M42 Lens To Pentax PK Mount Adapter Camera Ring For K-500,K-5II,K-5IIs,K-30,K-7 | eBay

That's a flanged adapter and won't allow for infinity focus. It might come in handy for quick lens changes while shooting portraits, though.

[boriscleto]

My adaptor is a "Pixco" from ebay.

You'll probably want to remove the spring clip. Friction is enough to hold it in place.

[Take-5-JB]

Get the real Asahi/Pentax one! I have two. I have 55mm, 135mm, 200mm, 300mm, and 400mm lenses, extension tubes, and a 2x teleconverter in M42. I have used them with my K2000, K200D, K5, K3, and K1 with no problems free held and on tripods. I have never had the flanged ones as they were flagged years ago with infinity focus problems and other issues.

JB

[mccririck]

The real ones are expensive on eBay.

[Thagomizer]

The real ones are expensive on eBay.

But worth it. Mine has never given me any trouble at all, and after reading the Forum stories about problems with lenses stuck on bodies using inferior, knock-off versions, I would not be tempted to use anything but the original adapter for anything requiring infinty focus. I recently picked up a black anodized flanged adapter that I will be using to mount M42 macro accessories like bellows and extension tubes, where infinty focus is not going to be needed. It does not have the spring clip that was warned about up-thread.

[MossyRocks]

I've never had a problem with any of my m42 lenses and accessories when using the Pentax m42 adapter. The largest and heaviest lenses I've used with it is a 400mm f/6.3 teleastanar and the 300mm f/4 Super Takumar, and I have had my 135mm f/2.3 Series 1 Vivitar on 2 full sets of extension tubes (112mm of extension) on it all without problems.

[kypfer]

The after-market M42-PK adaptors can be a right pain. I had one jam onto the body so hard I had to remove the mount completely from the camera so's to release the spring-latch "from the inside". I'll agree with the recommendation to remove the spring-latch completely then handle the lens carefully when it's mounted. A slightly stiff focussing mechanism can cause the bayonet to dismount unintentionally!
Myself, I acquired my Pentax original adaptor when I bought my *ist film camera. They were still sensibly priced in those days It still works perfectly!

[onlineflyer]

There's a genuine adaptor for sale in the marketplace. I have no relationship with the seller.

[stevebrot]

There's a genuine adaptor for sale in the marketplace. I have no relationship with the seller.

I saw that and the price is good too. Too bad the OP is in Britain.


Steve