Prior to purchasing this I wasn't sure if it would work with the Optio S12 although the description says it works with any Optio S series, the description then goes on to list only the older models of Optio S. In addition, one review on a website mentioned that the cable release is not compatible. I was pleased to find the system (including the cable release) connects flawlessly to my Pentax scope and XW14 eyepiece, and to my Optio S12 camera. The screw-on connection provides for a very stable setup, but the drawback is that it takes a second or two to screw the adaptor to the eyepiece, which is time I don't want to loose when I'm photographing birds as they are always moving! I therefore leave the adaptor permanently attached to the eyepiece which, with the scope eyepiece quick release, slides in and out very quickly - I simply use one eyepiece for observing, and the other one with the camera attached for photography.
Pros: Stable, good connection between camera and scope
Cons: Screw-on system
This review was written in the old system and had content requirements that are different than reviews written today.