To retrieve both HET and DIMM image quality histogram statistics, choose the year and trimester of interest.
Note: HET EE50 image quality statistics have been recorded from the LRS "pre" images since the beginning of 2001. DIMM image quality statistics have been recorded since trimester 2002-1. Dome louvers were installed in trimester 2002-2. Beginning with 2005-2, EE50 have been measured from the FIF guider camera images as well as LRS pre-images.
NOTE: On these plots the images are often cached by your browser, so looking at several of these can result in your viewing only one loaded before!