If usecal= Y, the uplinked
bright pixels and known dead pixels (within the current window)
are read from the CAL and those pixels
are ignored in computing the local median
and the threshold.
Optionally (includedeadpixels parameter)
one may include the dead pixels from the CAL in the output list.
This allows then to run badpix
with getnewbadpix=Y
getotherbadpix=N, to keep only the bright pixels active
in the current exposure while preserving the information about
dead pixels.
With usecal=N, the embadpixfind algorithm is not XMM specific at all and works on any images where the normal structure size is larger than 5 pixels.