A method for determining trailer angle includes determining angles of a trailer hitch relative to a data recording device via an angle measuring device while the trailer hitch pivots about a hitch ball of the device. While the trailer hitch pivots about the hitch ball of the device, trailer hitch information is determined responsive to processing of captured image data and responsive to determined angles of the trailer hitch. After determining trailer hitch information, data representative of the determined information is provided to an electronic device, which is disposed at a vehicle having a rear backup camera that has a field of view that encompasses a hitch ball of the vehicle and at least a portion of a hitch of a trailer hitched to the vehicle. Using the provided data, and responsive to processing of captured image data, an angle of the trailer relative to the vehicle is determined.