A lenticular image printer creates an image on received media having a series of lenticules with parallel axes. The printer includes a transport system adapted to move received media in an in-track direction substantially perpendicular to the axes of the lenticules. An alignment beam generator is arranged to transmit an alignment beam through the lenticules of received media such that the alignment beam is in-track position-modulated by the lenticules. Three position-sensing detectors are aligned in a cross-track direction perpendicular to the in-track direction so as to receive the position-modulated alignment beam whereby the position of the position-modulated alignment beam on the detectors provides an indication of the relative alignment of the axes of the lenticules and the cross-track direction.