To enable the camera to fire without a "lens" attached you must disable the shutter lock.
It's the first item in the third section of the custom menu.
See pages 92 and 97 of the owners manual.
Good luck with your pinole project,
Pete
scott
17-Nov-2006 21:49
hi there, i recently received a pinhole cover ( a "Rising Pinhole Obscura" adapter) for my 7D but i can't seem to use it. how did you get around the fact that the camera will not allow a picture to be taken, because each time i press the shutter button all i get is a message telling me there is no lense attached. i appreciate any advice because i am excited about trying this out!!! thanks!