A calibration cartridge (20) for an automated media library (60) comprises a cartridge case (30) having a calibration surface (35) and an electromagnetic transmissive channel (40). The electromagnetic transmissive channel transmits electromagnetic radiation incident upon the calibration surface at a radiation reception port (42) in a first position of the calibration cartridge so that the electromagnetic radiation travels interiorily through the calibration case and exits from the calibration cartridge at a radiation exit aperture (44) in a second position on the calibration surface. The calibration cartridge is usable in an automated information storage library which comprises plural cartridge-accommodating cells (64) and a drive (68).