== PS1 / IPP Time Errors ==

 * MJD-OBS (a TAI value in smf files) did not have the 2012.07.01 leap second in files for exposures after 2012.07.01 and processed between 2012.07.01 and 2012.11.09.  SHUTOUTC is OK.

 * Between 2015.04.26,16:45 HST and ~2015.05.12,12:00 HST the clocks on the camera readout computers drifted out of NTP lock, accumulating ~113s before the problem was fixed.  A table of corrections for the affected images was produced by Craig Rae by using information from one camera computers which did not drift.