Pentax PK mount to NEX adapter - unmounting question

[bruzzo]

Hello newbie here on the NEX system and I just got my first Pentax lens and a PK to NEX mount adapter (from Big-is). I mounted the lens smoothly and it fits very well without much loosening. But my question is how do I unmount it? I tried to turn it by force but seems doesn't work. There is a pin on the adapter and I tried to push it while turning just like the MD adapter but seem doesn't work as well.

I feel kind of stupid cause it should be pretty straight forward, but I don't want to risk damaging the lens and so safer to ask some experts here before doing anything .

Thanks.

[DigiChromeEd]

Slide the pin on the adaptor towards the camera body to release the locking mechanism and twist the lens to remove.

[bruzzo]

Job done thanks .

Kind of related to this too is, are there any tips on handling adapters two common problems on top of my head when using adapters are:

1. Well happen to M39 and M42 adapters mostly is when focusing and turning the focusing ring, the lens unscrews instead. Any tips on dealing with this?

2. Mostly on MD adapters and now Pentax too is the stiffness when trying to mount and unmount lenses especially unmounting. It really shows screwing marks on the rear of the lens. The marks are mostly not permanent and can be rubbed off with like a cleaning pen but just want to know if this is normal or I am doing it wrong and use too much force?

Thanks.