[arbib]

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Anyone permanently mount a M42>K adapter on an older lens?
And is it safe....I hate the setup that the mount has to come off separately when taking a lens off the camera without the mount adapter.

[wallyb]

It depends on how you mount the adapter to the lens. Personally, I don't see the point in paying $25-35 to get a new adapter for each M42 lens you want to use with your camera, but that's not my decision to make

[Ivan de Almeida]

I have one adapter, always in camera. I use only m42 lens and screw it into the body+adapter to replace the lens.

[pxpaulx]

It depends on how you mount the adapter to the lens. Personally, I don't see the point in paying $25-35 to get a new adapter for each M42 lens you want to use with your camera, but that's not my decision to make

With the official pentax adapter there is a small spring loaded hinge that would need to be removed - this keeps the adapter from being removed from the camera (I assume so that you can easily interchange different m42 lenses without having to un-mount the adapter). I don't know about cheaper aftermarket adapters, but assume at least some of them have something similar. So the adapter would probably need some work, but after that it wouldn't be a problem.

[dlacouture]

Well, I had one adapter for each m42 lens I got, and it's waaaaaay better to handle...

Only problem is that it's free to rotate, as you have to remove the little metal spring holding it into the K-mount...

So this leaves you with the following choice:
- use the flanged variety, so it will lock in just like a regular P-K lens, but you lose infinity focus (not a big problem if you do portraits only)...
- drill a hole into the lens (great with cheap lenses, my J-9 got a locking hole two days after reception!)
- do nothing and be really careful while focusing, or your lens will go crashing on the floor...

[arbib]

Thanks so far for the replies..
I only intend to buy one or two M42 lenses...in the short tele range...I have found what appears to be an adapter that can stay on the lens at all times, and the lens can then be removed like a PK lens -- Together --

Metal Mount M42 to Pentax PK Mount Lens Cam Adapter - eBay (item 230369984186 end time Sep-21-09 07:55:08 PDT)

If this is true....I send emails to confirm this...This is what I want.

Anyone have one of these or similar?

[noblepa]

So far, the only M42 lens I use on my K10D, is my old Super-Takumar 50mm, f/1.4, so I only have one adapter. It is a third-party model that fits flush inside the camera, so no problem with infinity focus.

Despite the warnings of some, I have never had any problems with my third-party adapter. The locking spring clip fell off, so I usually just leave the adapter on the lens. There is plenty of friction between the adapter and the camera to prevent the lens/adapter from accidentally rotating and falling out. But, there is not so much that removal is difficult, either. And, the S-T lens remains firmly screwed into the adapter, just as it did on my Spotmatic, so there is no danger there, either.

For those with a genuine Pentax adapter, is the fit so much smoother that there really is a danger of the adapter becoming loose, if the spring clip is removed?

[noblepa]

Thanks so far for the replies..
I only intend to buy one or two M42 lenses...in the short tele range...I have found what appears to be an adapter that can stay on the lens at all times, and the lens can then be removed like a PK lens -- Together --

Metal Mount M42 to Pentax PK Mount Lens Cam Adapter - eBay (item 230369984186 end time Sep-21-09 07:55:08 PDT)

If this is true....I send emails to confirm this...This is what I want.

Anyone have one of these or similar?

The one you link to has the flange that sits outside the camera mount. This adds a mm or two to the thickness and prevents the lens from focusing to infinity. For a telephoto, that is probably not a good thing.

Here's one that sits flush inside the camera mount, allowing infinity focus.

Pentax M 42 to K Mount Adapter - eBay (item 260476760685 end time Sep-20-09 14:50:54 PDT)

[arbib]

The one you link to has the flange that sits outside the camera mount. This adds a mm or two to the thickness and prevents the lens from focusing to infinity. For a telephoto, that is probably not a good thing.

Here's one that sits flush inside the camera mount, allowing infinity focus.

Pentax M 42 to K Mount Adapter - eBay (item 260476760685 end time Sep-20-09 14:50:54 PDT)

That is the kind that has to stay on the camera, and be taken off separately. I had one, and it was a real pain to use the tool to get it off my Film body. Thanks for INF info too.

[bogiesbad]

A member here discusses the different adapters and has a tutorial on making a cheap adapter "permanent". I found the article very informative. A search for "hinman" will lead you to his excellent blog.

[arbib]

The one you link to has the flange that sits outside the camera mount. This adds a mm or two to the thickness and prevents the lens from focusing to infinity. For a telephoto, that is probably not a good thing.

Here's one that sits flush inside the camera mount, allowing infinity focus.

Pentax M 42 to K Mount Adapter - eBay (item 260476760685 end time Sep-20-09 14:50:54 PDT)

A member here discusses the different adapters and has a tutorial on making a cheap adapter "permanent". I found the article very informative. A search for "hinman" will lead you to his excellent blog.

Thanks for the link search.
So the REAL Pentax adapter is a lot easier to dismount from the body..Good to know.

[noblepa]

That is the kind that has to stay on the camera, and be taken off separately. I had one, and it was a real pain to use the tool to get it off my Film body. Thanks for INF info too.

That was the first one I found in my eBay search. It happened to be a third party adapter.

When I got my third party adapter, it took a little while to get used to using the tool. After I got the hang of it, though, I could remove the adapter with almost anything that was handy, including a ballpoint pen tip.

However, as I said in the post just previous to the one you responded to, the spring clip on my adapter fell off. Many people remove them anyway. Once it was off, the adapter could be removed with the lens. Since I only have one M42 lens that I ever use on my K10D, I leave the adapter on that lens, effectively turning it into a K-mount lens. When I want to remove it, I simply rotate the lens about 1/8 turn counterclockwise and it pops off in my hand, with the adapter still firmly attached to the lens.

So, no, it does not have to stay attached to the camera.

Many people claim that the genuine Pentax adapter is much easier to remove. I have never used one, so I can not comment on that. I have never had any trouble with my third party adapter.

Any adapter that will allow infinity focus is going to be designed to stay on the camera. They all have a sheet-metal spring clip to lock the adapter in place, since M42 lenses lack the hole for the lens lock pin. Some adapters are machined to closer tolerances than others, but all that allow infinity are of the same basic design.

[raymeedc]

I shoot exclusively with manual focus Pentax lenses, one set of M42 screwmount Takumars & one set of early K mounts. Such being the case, I shoot with two identical DSLRs, one with a permanently mounted original Pentax adapter, used as a dedicated screwmount body.

[Blue]

Keep in mind that in permanent modifications to a lens WILL effect its resale value in the future. With some lenses, it may not be a big deal. However, some are more rare and valuable.

[arbib]

Keep in mind that in permanent modifications to a lens WILL effect its resale value in the future. With some lenses, it may not be a big deal. However, some are more rare and valuable.

Understood.....If I got a more popular M42 lens...lets say a Zeiss or a rare Russian M42...I would leave it be..
But I have heard that a OEM Pentax Adapter with the Spring taken out works quite well leaving it on the lens, and can still be taken off the lens when needed.