Exactly as
steephill and
pepperberry farm … I have an OEM adaptor fitted semi-permanently to one of my bodies (the *
istDS at the moment) and if I want to play with my screw-fit lenses I simply grab that body and "go basic"
The OEM adaptor is very well made, it never jams on the camera and is designed to be released just using a fingernail … the slightly higher price is well worth the peace of mind!
Unfortunately I am one of that rare breed that does read the manual, thoroughly and extensively, so I rarely have problems