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Default epoch for object RA / Dec

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HOA's picture
Default epoch for object RA / Dec

Does VPHOT assume a particular epoch for object coordinates during data entry?

I've experimented a little with J2000 and JNOW (e.g. 2011) when entering object coordinates. It seems that I get more plate solutions using J2000 rather than JNOW. Hence, I assume that the VPHOT default epoch is J2000.

My setup writes JNOW coordinates to the FITS header; hence, my interest in knowing which coordinates VPHOT actually uses. I've really enjoyed using VPHOT!

Andy Howell (HOA)

kge's picture
Default epoch for object RA / Dec

Yes. VPHOT uses PinPoint to plate solve images, and PinPoint assumes J2000.


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