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How to convert solar image from telescope into spherical coordinates

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a a

Oct 7, 2022, 3:32:27 PM10/7/22
Looking for JavaScript tool to work for HTML5 on smartphone in web
browser to get 2D flat image from a telescope live processed into 3D
spherical image to generate heat maps and calculate total energy emitted

What data structure is fit to save spherical imaging ?

In theory, I can process 2D flat image saved into data array and filter
out pixels representing image of the Sun (solar disc) for postprocessing
and for any given pixel (x,y), I need to calculate its distance from the
center of the solar disc and multiply its grey or RGB value by a reversed
factor, reducing the area of a circle on the surface of a sphere when
projected onto a 2D flat surface.

Ok, in theory and practice I can wait hours to have sunspots or sunspot
groups detected at the edge of the solar disc to turn and move more into
center of the disc for the verification, the above concept is fair, not
generating extra overheads in sunspot energy values

Let me know your opinion

thank you \ darius

[[Mod. note -- There is a software package HEALPix which could probably
be used to do this, but this may be "overkill" and it would certainly
take some programming. I downloaded a copy of HEALPix in 2016 (but never
did anything with it); at that time it had bindings for C, C++, Fortran 90,
Python, IDL, and Java (but not Javascript). My notes say that back then
it lived at
and was described in some detail in the paper
G\'{o}rski et al,
"HEALPix: A Framework for High-Resolution Discretization
and Fast Analysis of Data Distributed on the Sphere"
Astrophysical Journal 622, 759
preprint: arXiv:astro-ph/0409513
-- jt]]
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