DPCC Time stamp from FITS header

Posted by Mark Salisbury on Aug 05, 2018; 5:52am
URL: http://astroimagej.170.s1.nabble.com/DPCC-Time-stamp-from-FITS-header-tp1031.html

Hello

I am trying to find out if it is possible to change the FITS header field used to determine the UTC-based start of exposure time in DPCC?  One of the telescopes I am using has recently been upgraded with a GPS time unit and shutter trigger to provide very accurate timing but the new GPS determined start time is being added to the FITS header with a different FITS keyword - "GPSSTART".  I would like to use this time stamp to determine BJD_TDB rather than the usual "DATE-OBS" keyword.

Many thanks
Mark Salisbury