This paper discusses the measurement and correction of line spacing errors in laser recorders caused by residual fabrication tolerances in the face-axis angles of multi-faceted mechanical scanners. These residual angular errors are typically the chief source of line to line spacing errors in systems employing multi-faceted scanners. Apart from the fact that a periodic line structure produced in the film which is objectionable from an aesthetic viewpoint, the spacing errors decrease the MTF of systems having 10 micron line spacing, or less, which is becoming increasingly common in current equipment. A new application of a previously known art is used to correct angular errors in a multi-faceted scanner to an accuracy of 0.1 arc-second (1 part in 2,000,000). The correction technique appears to be limited only by the resolution of the measurement.