I converted this camera (Ixus 40). It was fairly easy to do; but after reassembling I saw that it wouldn't focus. I eventually ended up adding a couple of pieces of very thin glass (where the IR blocking filter was) to get the focus back. I'm thinking of doing another camera, but would prefer to do one that will focus without further modifications. Can anyone tell me which camera(s) do not need modification after removing the IR blocker?