... The PPS pipeline is by design not intended to process EPIC or OM exposures performed using non-science modes or filters. ... A typical and rather frequent example of such exposures are the EPIC closed filter calibration exposures . At least one of such exposures in each EPIC camera is normally taken at the beginning of each XMM-Newton orbit. ... These closed filter EPIC calibration exposures represent therefore additional science OM and RGS exposure time. ... Pages maintained by SAS librarian . ...