< snip >
> I tried Registax with wine some time ago without much success. Things
> might have improved since then so I must try again. Meanwhile there is
> an application called AstroStack, freely available on the Web, which
> does what you need for stacking multiple photos. Also, the usual tools
> such as contrast, brightness, sharpness etc are readily available and
> not difficult to use in Gimp.
I came across this which you may find interesting.
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