Plotted entries from OPSLOG files in UVES report MOS_FMTCHK_GratPos_PhysM_dY_DHC, plot 4:

DATE       MJD-OBS      parameter values
==========================================================================
2008-12-23 54823.520667 0.0924	psR580P1L_P
2008-12-30 54830.450954 0.3261	psR580P1L_P
2009-01-04 54835.559778 0.0700	psR580P1L_P
2009-01-06 54837.645245 0.1932	psR580P1L_P