Hi Adam,
Welcome to the BAA Forum! That sounds like an excellent telescope and those are great images.
I am not sure I understand your question, but I’ll have a go at an answer.
With colourising I would be surprised if the algorithm in Astroart does anything other than assign predetermined colour values in RGB based on intensity to make it look nice, rather than anything to do with velocities. It is possible it has a template for the Sun, and varies the colour based on the location on the solar disc. The key point is the monochrome pixel values contain no data that can be converted into a velocity. I expect the temperature has nothing to do with it, other than cooler parts of the Sun such as sunspots emit less light.
All this said, if you are able to tune the H-alpha pass band in your telescope, then you might be able to sample different velocities relative to the H-alpha rest wavelength.
Best wishes,
Andy
British Astronomical Association
Supporting amateur astronomers since 1890
