In some examples, a printer includes neighboring nozzle arrays extending across a print zone, each nozzle array of the neighboring nozzle arrays extending along an axis and comprising a first section of nozzles and a second section of nozzles, wherein the second sections of the neighboring nozzle arrays overlap defining an overlap region and the first sections of the neighboring nozzle arrays define non-overlap regions. A controller is to cause printing of a test pattern using the neighboring nozzle arrays, the test pattern comprising a first pattern printed by the second sections of the neighboring nozzle arrays in the overlap region, and a reference pattern printed by a first section of the first sections of the neighboring nozzle arrays in a non-overlap region of the non-overlap regions, receive detected characteristics of the printed test pattern, compare the characteristics of the printed test pattern in the overlap region and in the non-overlap region, and derive alignment information based on the comparing.