ESO WIDE REVIEW, April 2000


Astroclimatology of ESO Sites	ESO WIDE REVIEW M. Sarazin, April 2000, 8/10

Astroclimatology of ESO Sites

ESO WIDE REVIEW

M. Sarazin, April 2000, 8/10

Comparing external DIMM seeing to UT focal Image Quality (IQ) is a tool for controlling the performance of each telescope, enclosure and instrument. Such a work should be systematized with a direct access to IQ data produced both by active optics image analysis and pipeline quality control processes

COMPARING DIMM SEEING TO UT IMAGE QUALITY

Comparison of DIMM seeing (Y axis) with FORS Science Verification Image Quality (X axis, data processed by SV team): DIMM converts image motion into large telescope seeing with the assumption of an infinite outer scale of the turbulence. UT images turned out about 10% better than predicted by DIMM, confirming the finite character of the outer scale. Correcting for that effect is possible by removing from the DIMM the share of the tilt of an 8m aperture.