Originally posted by GUB Na na that hole is drilled in the lens base. It is outside the adapter. That is why the noninfinity adapter is better (if you don't require infinity)
Thanks for clearing that up (should have known, really, stupid me). However, not having infinity is a bit of a deal-breaker for me - except possibly for a macro lens. I'm sure someone with the appropriate skills could modify the helicoid to suit, but that person is not me.
On the other hand, a lens that focuses PAST infinity would be ideal in this case (the question is whether it can reach far enough past in its native state to cover the loss).