A light reference system for use with a rail vehicle comprising: a first rail follower, a second rail follower and a third rail follower respectively couplable to a rail vehicle, the second rail follower being disposed between the first and third rail followers (200, 400); a plurality of first light sources (212, 214, 216) disposed on the first rail follower and configured to emit light towards the second rail follower; a plurality of second light sources (412, 414, 416) disposed on the third rail follower and configured to emit light towards the second rail follower; a first camera disposed on the second rail follower, the first camera having image sensors configured to receive the light emitted by the plurality of first light sources and generate a first image based on the light received from the plurality of first light sources (212, 214, 216), the first image showing a plurality of first light source objects (602, 604, 606) corresponding to the plurality of first light sources (212, 214, 216); a second camera disposed on the second rail follower, the second camera having image sensors configured to receive the light emitted by the plurality of second light sources (412, 414, 416) and generate a second image based on the light received from the plurality of second light sources, the second image showing a plurality of second light source objects (612, 614, 616) corresponding to the plurality of second light sources (412, 414, 416); and a processing device configured to: receive the first image from the first camera, and receive the second image from the second camera; perform a measurement, based on the positions of the plurality of first light source objects (602, 604, 606) and plurality of second light source objects (612, 614, 616) shown in the first image and second image, to determine a vertical and lateral position of the second rail follower with respect to at least one of the first rail follower and third rail follower; and determine a lateral chord offset, a vertical chord offset, and a twist in a pair of rails. a first rail follower, a second rail follower and a third rail follower respectively couplable to a rail vehicle, the second rail follower being disposed between the first and third rail followers (200, 400); a plurality of first light sources (212, 214, 216) disposed on the first rail follower and configured to emit light towards the second rail follower; a plurality of second light sources (412, 414, 416) disposed on the third rail follower and configured to emit light towards the second rail follower; a first camera disposed on the second rail follower, the first camera having image sensors configured to receive the light emitted by the plurality of first light sources and generate a first image based on the light received from the plurality of first light sources (212, 214, 216), the first image showing a plurality of first light source objects (602, 604, 606) corresponding to the plurality of first light sources (212, 214, 216); a second camera disposed on the second rail follower, the second camera having image sensors configured to receive the light emitted by the plurality of second light sources (412, 414, 416) and generate a second image based on the light received from the plurality of second light sources, the second image showing a plurality of second light source objects (612, 614, 616) corresponding to the plurality of second light sources (412, 414, 416); and a processing device configured to: receive the first image from the first camera, and receive the second image from the second camera; perform a measurement, based on the positions of the plurality of first light source objects (602, 604, 606) and plurality of second light source objects (612, 614, 616) shown in the first image and second image, to determine a vertical and lateral position of the second rail follower with respect to at least one of the first rail follower and third rail follower; and determine a lateral chord offset, a vertical chord offset, and a twist in a pair of rails. receive the first image from the first camera, and receive the second image from the second camera; perform a measurement, based on the positions of the plurality of first light source objects (602, 604, 606) and plurality of second light source objects (612, 614, 616) shown in the first image and second image, to determine a vertical and lateral position of the second rail follower with respect to at least one of the first rail follower and third rail follower; and determine a lateral chord offset, a vertical chord offset, and a twist in a pair of rails.