FOC Instrument Science Report 056 3/2/92 "Observations to Determine the FOC Focus" by P. Hodge Abstract excerpted from report: This report describes Science Verification observations taken at different positions of the refocussing mirror mechanism. Three tests of focus were used, and all three gave fairly consistent results. Significant changes in focus quality were seen at both f/48 and f/96, with the best focus for f/48 near the nominal position and the best focus for f/96 near or below the lower limit of the range.
