As long as the picture is from a cam that RLC broadcasts is not against forum rules to post but if you have a RLC account you'll likely lose it as RLC will ban your account and prevent you from further access to their site. No matter whether there is identifying watermarks or no watermarks are showing RLC can still detect who the poster and the account holder it was posted from.
If the picture is from an outside source such as from any Social Media, Google Earth, GE Street View, then it violates the forum rules and the pictures will get removed and a warning will likely be given.