This plot monitors the counts generated by the halogen lamp in ZIMPOL polarimetry flats. (A lamp flux in ADU/sec is not provided by the pipeline).
Only polarimetric direction = zero and cycle  = odd signal is monitored. 
The following setups are covered:

<ul>
<li> V filter,   DIT, NDIT = 4.0, 10
<li> N_R filter, DIT, NDIT = 2.0, 20
<li> N_I filter, DIT, NDIT = 2.0, 40
</ul>
The plot contains four boxes, which shows the counts 
for both read modes (SlowPolarimetry and Fastpolarimetry) and for both
detectors.