This parameter is determined from an overscan-subtracted calibration
lamp exposure in LSS mode (taken with the template
FORS2_lss_tec_flatLampcheck). The total signal is integrated and
normalized by the exposure time and the total number of original CCD
pixels (keeping into account possible binning). More information can
be found in the <a
href="http://www.eso.org/observing/dfo/quality/FORS2/qc/lamps_qc1.html">plot
tutorial</a>.

The setup of the lamp check is G300V, GG435 and 1arcsec slit.
<ul>
<li><b>FFB34</b>
Monitoring the lamp flux of the two 
high brightness blue halogen lamps FlatBlue+3 and FlatBlue+4.
These lamps are used to generate spectroscopic flats in blue (G300V, G600B)  spectroscopic setups.
</ul>

</font><p><font size="2"><b>NOTE:</b> On April 18, 2016 the FlatBlue+4 lamp was disabled and later taken out of the instrument's calibration unit.
Since then, only FlatBlue+3 lamp is used for spectroscopic flats. <br>
On November 15, 2016 the sub-plots relevant to the FlatBlue+4 lamp were removed.

</font><p><font size="2">
<i>DB Name: fors2_lamp_chk <br>
TPL.ID: FORS2_lss_tec_flatLampcheck <br>
QC1 DB parameter: flux
</p></i>