Plotted entries from OPSLOG files in NACO report DAILY_DARKRON, plot 4 (data set darkDCR_HC):
(DATE changes at 21:00 UT or MJD-OBS = xxx.875)
DATE       	MJD-OBS      	values
====================================================
2013-05-14	56427.482311320000000	2.81000018119812
2013-05-15	56428.469362980000000	2.91333317756653
2013-05-16	56429.359979030000000	2.72333335876465
2013-05-17	56430.362984550000000	2.72666668891907