Abstract: Apparatus for synchronizing a first video signal corresponding to a first image and a second video signal corresponding to a second image, each of the first and second video signals including vertical and horizontal synchronizing signals, including a video camera which produces the first and second video signals and which generates vertical synchronizing signals for the first and second video signals in response to a negative-going edge of a pulse signal supplied thereto; a storage device which stores the first video signal produced by the video camera; a synchronizing signal generator which supplies vertical and horizontal synchronizing signals synchronized with the corresponding signals of the first video signal when the video camera is viewing the second image; and a monostable multivibrator connected between the vertical synchronizing signal terminals of the synchronizing signal generator and the video camera, and operative during viewing of the second image to produce and supply said negative-going edge