I am about to purchase this adapter to allow me to use my old Pentax 50mm f1.4 m42 screw-mount lens on my Pentax K-X. I would appreciate it if someone can confirm that this is the right adapter for my camera and lens set-up. I am pretty sure this is the right adapter, but just want to be sure, since there are many different companies making there own versions. http://www.pentaxwebstore.com/detail/PTX+30120
Thanks