[Aavso-photometry] FITS and observation time

[Jeff Hopkins]

Normally I observe long period eclipsing binaries where precise time 
to the second or millisecond is not a factor. Recently I have started 
a mentor project using the fast eclipsing binary sz Herculis. I am 
using AutoStar and found the FITS time indication is off. It seems to 
be the time the file is saved. I started a one-shot 15 second 
exposure at 05:02:30. The end time should have been 05:02:45 or 
close. The FITS Header indicated 05:02:57.

If the difference is fairly constant, it could be compensated for. 
However, things get more complex when images are stacked and during 
the stacking when some images are not stacked due to poor quality.

How has this been handled by the AAVSO?

Jeff
-- 
Jeff Hopkins
HPO SOFT
Counting Photons
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