Filename                               Reason     Bkg         V      RCAM      TCAM   Sigma
20211123.182626.ucomp.656.l1.p5.fts        16    28.1     16.98       0.2       0.2     NaN
20211123.183040.ucomp.656.l1.p5.fts        16    28.3     27.89       0.2       0.2     NaN
20211123.183453.ucomp.656.l1.p5.fts        16    28.5     41.12       0.2       0.2     NaN
20211123.191704.ucomp.656.l1.p5.fts        40    -0.2      0.01    9077.3   10839.0     NaN
20211123.191818.ucomp.656.l1.p5.fts        40    -0.2      0.01   11678.5   10949.4     NaN
20211123.191932.ucomp.656.l1.p5.fts        40    -0.2      0.01   10669.8   11375.9     NaN
20211123.192046.ucomp.656.l1.p5.fts        40    -0.2      0.01   12361.0   11100.3     NaN

GBU bitmask codes
Code    Description
    1   spar guide control loop is below threshold (0.99)
    2   spar guider intensity below threshold (0.9 * 9.256 * exp(-0.05 * secz))
    4   median background is above threshold (45.0)
    8   median background is below threshold (5.0)
   16   spurious Stokes V signal is above threshold (8.0)
   32   the chi-squared of the occulter fit is above threshold (800.0)
   64   the difference of the image with the median is above threshold (3.0)

* indicates that the threshold values changed on the day