NOVA 120 Pointing model user manual
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Each of these models can be enabled / disabled, even the mount been online to the NOVA mount software. This can be
interesting for testing purposes. Also refraction speed can be set or unset, because refraction is causing pointing errors
(compensated by the software, but also tracking speeds errors).
4. Final checks
It can be interesting to check how this pointing model actually improves pointing accuracy of the telescope. This can be
performed by manually pointing a field, or an object. At first pointing, synchronization with a bright star can be achieved
and will not jeopardize point model performance.
Then the same procedure of field scans can be achieved in both sky hemispheres (before and after meridian) to check
how the pointing model is actually improving the pointing accuracy.
The next screen capture is showing residual errors for each field that has been scanned. Some fields are exhibiting just
10 arcsec pointing error, other up to 2 arcmin, for instance. This is more than expected, but always the case because
different fields have been used.
It means, in this sample, if the telescope focal length would be increased from 1.5 m to 63 m using the same CCD
detector, in all cases, in all places over the Sky, targets will be inside the field of view of the camera.
Also same checking can be performed by long unguided exposures with speed model enabled.
