Author Topic: SIP  (Read 153 times)

Offline hvb356

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SIP
« on: 2019 January 09 08:39:07 »
Dear,

on my wishlist is the storage of the SIP (Simple Imaging Polynomial) polynoms in the FITS header after plate solving.

Thank you

Hartmut
TOA-150, ML8300, CFW2-7 w. Astronomik HaLRGB, PDF, EM-400, guiding FS-60 + ST402, ASCOM bsd. image acquisition

Offline Andres.Pozo

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Re: SIP
« Reply #1 on: 2019 January 09 09:49:48 »
The distortion correction in ImageSolver uses 2D splines instead of polynomials because splines are a much better solution.

It would be possible to generate a polynomial approximation and store it in SIP. However, I have no time and no motivation to do it. If anyone wants to do it...
 
Andrés.

Offline hvb356

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Re: SIP
« Reply #2 on: 2019 January 09 10:27:00 »
Hello Andres,

thanks for your fast answer.
Well, can you provide me a good document, which describes the math? The transformation from image coordinates to celestial coorninates is not the problem. The follow up correction with the splines (*.csv) is currently out of my focus.

Best regards

Hartmut
TOA-150, ML8300, CFW2-7 w. Astronomik HaLRGB, PDF, EM-400, guiding FS-60 + ST402, ASCOM bsd. image acquisition