A method of manufacturing a glassy optical preform is disclosed that includes providing a preform having a silica soot layer and then sintering the soot layer into a glassy layer, and water is selectively added to the preform by exposing the soot layer to a gaseous water-containing atmosphere during the sintering step. The access reader contains a programmable microcontroller, DCDC converter, regulator, Opto-Isolators and LEDS, and an RF modem. An imaging plane perpendicular to the line intersecting the optic centers of the first image and the second image is then determined and used to generate a first rotation-cancelled image and a second rotation-cancelled image.