From Richard Schwartz:
Two changes have been made in building the calibrated_eventlist data 
structure that is used for all imaging:
1. The error term of the solar aspect system (SAS) solution is now 
checked and if it is too large those elements of the data structure have 
their counts and livetime set to 0 so they won't be used in making 
images.  This check runs all of the time and cannot be disabled other 
than by compiling hsi_calib_eventlist_raw__define.pro in 
hessi/idl/util.  Most of the time it has no effect except when the spin 
axis becomes so close to the limb that the aspect solution is degraded.
2. There is now a correction that can be used to make images through 
attenuator state changes. The attenuator state correction is folded into 
the GRIDTRAN field of the hsi_calib_event structure for all valid 
attenuator states after the initial one during the imaging time 
interval.  It is enabled if the control parameter, 
CBE_MULTI_ATTEN_THRESHOLD, is changed from its default of -1 and the 
minimum energy of the image (energy_band[0]) is greater or equal to this 
value.  Also, when this is enabled and USE_FLUX_VAR is set, then the 
demodulation routine that determines FLUX_VAR by determining the flare 
time variation uses a new version that is considered more robust.  After 
May 1 we will probably use this new demodulation routine in all cases to 
determine FLUX_VAR.