Ummm,
The Preferences of iChat or Messages can start up the camera you have if the Preferences were left on the Video and Audio pane. It takes the title of the pane.
If the Preferences window shows the Video and Audio pane it has a Preview of what the camera sees.
Under this is a green response bar for the audio (your In Audio).
It has drop downs for the Mic selection, the camera if you have two cameras, a BlueTooth headset option and the Bandwidth Limit.
Example Pic
The man in the pic and the background may vary 😝 😀 .
7:33 PM Saturday; May 11, 2013
iMac 2.5Ghz 5i 2011 (Mountain Lion 10.8.3)
G4/1GhzDual MDD (Leopard 10.5.8)
MacBookPro 2Gb (Snow Leopard 10.6.8)
Mac OS X (10.6.8),
Couple of iPhones and an iPad
"Limit the Logs to the Bits above Binary Images." No, Seriously