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Hubble Space Telescope
FOC Instrument Science Report 056

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.