Plotted entries from OPSLOG files in VIMOS report MASK_ZERO, plot 7, data set parY0Q3:

DATE       MJD-OBS      parameter values
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2008-11-20 54790.928079 1388.99874616441	parY0Q3
2008-11-21 54791.890068 1389.1645453397	parY0Q3