[evalon]

Hi Pentaxians,

I'm really frustrated and hope one of you can help with this ... It is so that I recently bought an SMC 24mm f2.8 lens and mounted it on the adapter I had bought for my Sony NEX-5 camera. Mounting the lens on the adapter was a tight fit (something I also noticed on the Pentax ME Super camera that came with the lens) but I added just a tiny bit of olive oil on the metal parts and then slid the lens onto the adapter. This worked and at the end of rotating the lens onto the adapter I noticed a low "click" and then the lens was there.

However, now I cannot get the lens off of the adapter again .... The lens is not mechanically "locked" on the adapter - it can be moved ever so slightly relative to the adapter - maybe ½ mm - but it is as if there's a mechanism - the "click" - that somehow prevents it from coming loose. And besides the knob on the adapter, which doesn't appear to make any difference in this context, I can't see any release mechanisms on either the lens or the adapter I bought.

I've attached a couple of pictures so that you can see what the lens + adapter looks like.

And - help is really appreciated!

Jesper

Attached Images

     

[bobpur]

Hi

I have the same one, slide the knob towards the camera side. It has a small pin that locks the lens in place.
You might have to jiggle the lens a bit to move the knob but it will move, then while holding it back twist the lens .

[hoanpham]

That can happen with both cheap and expensive adapters.
I can't help you to unmount the adapter, but if you somehow can get it off,
You need to unscrew the adapter and sand it a bit with a very fine sand paper, then assemble the adapter and test it agains some cheap stuff like tubes/defected lenses/tc etc.
Just sand a bit, do not take too much. Cheap adapters does not have bayonet springs and depend on metal-metal resistance to keep the lens in place without play. Using force may destroy the lens.

[hoanpham]

Try to press the knob on the adapter away from the lens and twist the lens. That s what bobpur tried to tell.

[evalon]

Hi both,

You are magnificent! I did exactly what you suggested and off the adapter came - no trouble at all :-)

As it is the adapter didn't come with any kind of instruction so I didn't know if the knob was for locking the lens on the adapter (tightening it) - and I didn't observe it moving towards the camera while rotating it - but now it works. Yeehaaaahhh - appreciated :-) Will send you a friendly "thank you" tonight before sleep comes my way ;-)

BTW the lens came off quite easily now - might be due to the olive oil - but mounting other lenses is tight again so will try the sandpaper. Thanks again!

Greetings,

Jesper

[bobpur]

Don't sand anything !
Unless you REALLY clean everything it could get into your camera and really mess things up.
It will loosen up a bit, anyways it is better than having a loose fit.

[evalon]

Hi Bobpur,

Thanks for airing your caution, and as it is I yesterday was able to gently squeeze the surfaces that hold the lens into a slightly less firm grip on the lens. So it works now and even well so.

So I sense being pleased ;-)

Thanks again both of you!

Jesper