There is no little penta prism in there. The construction is similar to a "spy glass" (Galilean telescope) in that it doesn't developed an image, you just look through it backwards (optically speaking). Look at it like a wide angle adaptor similar to those built for the normal lens of a cheap camera - only for your eye. Regards, Bob.. From: "Gregory Fraser" <Gregory.Fraser@pwgsc.gc.ca> > Does anybody know why the image in an apartment door peep-hole is not > inverted? Is there a tiny little penta-prism in there?
