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Old 13-02-2014, 08:42 AM
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Shiraz (Ray)
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Join Date: Apr 2010
Location: ardrossan south australia
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Good question Geoff.

The way I see it is that stars are actually hard points of light with no size, but the atmosphere (and to a lesser extent your scope/mount) blurs them into fuzzy balls with nearly Gaussian profiles and with size depending on brightness. The basic question is - do you want them to look like they really are or as they look after being distorted by the atmosphere?

Deconvolution attempts to get stars back to what they really look like, but it cannot restore them entirely to points due to saturation and noise. You end up with smaller hard edge spots rather than unresolved points (and they are likely to be saturated). In my view, this is just as valid a representation as soft edged spots, but convention is that soft-edged, unsaturated fuzzy balls are “right” (possibly a carry-over from the days when everyone used refractors). As Greg points out, it is fairly easy to tweak deconvolved stars to look how you want and hard edged spots can be softened with a simple Gaussian blur to look “natural”. You can overlay the star colour from the original image should that be important to you. Of course, you will be deliberately getting further away from reality, but the result will look more conventional and colourful. Your choice. regards Ray

Last edited by Shiraz; 13-02-2014 at 06:53 PM.
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