Hello,
Are the ra and dec coordinates as read from the mount and recorded in the FITS header - for the beginning of the exposure?
Patrck.
FITS Header coordinates
Re: FITS Header coordinates
Hello,
no, they are read from the telescope when the image is downloaded.
The only data that is recorded at the start of the exposure is the time.
Fabio.
no, they are read from the telescope when the image is downloaded.
The only data that is recorded at the start of the exposure is the time.
Fabio.
Re: FITS Header coordinates
Fabio,
Might it be possible to include the Sidereal Time property read from the mount as a Write to FITS header option?
Regards,
Patrick.
Might it be possible to include the Sidereal Time property read from the mount as a Write to FITS header option?
Regards,
Patrick.
Re: FITS Header coordinates
Yes, but why "read" from the mount ? Instead it can be automatically calculated from the other data.
Is this to be read by a software or a human? (there is no a standard FITS keyword for LST, someone uses decimal (10.423242) others h-m-s (10:23:56)).
For humans it could be interesting to express it as mid of exposure.
Fabio.
P.S. for a given image here is a script to show the sideral time:
Is this to be read by a software or a human? (there is no a standard FITS keyword for LST, someone uses decimal (10.423242) others h-m-s (10:23:56)).
For humans it could be interesting to express it as mid of exposure.
Fabio.
P.S. for a given image here is a script to show the sideral time:
Code: Select all
lst = SideralTime(Observatory.Longitude, Image.JD) ' or just Image.MidJD
print "Sideral time = "; RaToString(lst)
Re: FITS Header coordinates
Fabio,
I noted ‘read from the mount’ as merely a suggestion to pssibly match your explanation.
Very happy to have the option to calculate and record the local sidereal time in the image header using other data - at download. This also makes the time stamp the same (at download i.e. the end of the exposure) for all such data?
I do spectra analysis using IRAF and IRAF tasks accept the st value as a sexagesimal strung with twodecimals in the seconds (a separate email sent).
Regards.
Patrick.
I noted ‘read from the mount’ as merely a suggestion to pssibly match your explanation.
Very happy to have the option to calculate and record the local sidereal time in the image header using other data - at download. This also makes the time stamp the same (at download i.e. the end of the exposure) for all such data?
I do spectra analysis using IRAF and IRAF tasks accept the st value as a sexagesimal strung with twodecimals in the seconds (a separate email sent).
Regards.
Patrick.
