1. A method of configuring a multiple channel imaging head for imaging a regular pattern of features, the method comprising: determining a number of channels for imaging such that only one or more complete pattern features will be imaged in a single scan of the imaging head; and configuring the imaging head in accordance with the determined number of channels, wherein at least one of the multiple channels is not imaged, the at least one of the multiple channels being located between the first channel imaged and the last channel imaged in the single scan.