I was looking for a wireless remote and have a few questions. Any major difference from canons RC-1, RC-5, or RC-6. B&H has the RC-6 but I see no specifications. Will I have any problems trying to use this from behind the camera or out of the picture, sorta speak ? My main reason for the controller is for shooting without camera shake but if I can get away with it, using the wireless feature for shots including me without having to press and run would be good. Do I need wired and wireless ?