Hey guys, I was wondering whether or not there was a distinction between off-camera nd off-screen tags added to dialogue. At first, I assumed that it was used to indicate whether a character is present in the scene or not. For example, "O.S." would be used for a phone call because the speaking character is not present in the room, but "O.C." would be used when a character is in the room, but simply not in frame. However, after reading a few scripts, it seems that they mean the same thing, and it is up to the writer which they want to use. Is there a convention dictating how these are used?