Hi!
Luckily the whole week from 22nd to 28th August we had perfect weather here in Austria.
No Clouds at all!!! So i could capture on August 26th the Comet Garrad together with M71.
To make the image processing less complex i captured M71 already on the 23rd of August
without the Comet!
Both results were aligned and stacked seperately and finally
mixed together on the right position.
Hier the result:
A full size version can be found here:
http://www.werbeagentur.org/oldwexi/gallery_deepsky/Garrad_M71_man.jpg All image processing steps werde done with PixInsight. (Except the stacking of the comet itself).
Data:
QHY8 Color-CCD on C14 with Hyperstar, 675mm focal length, NO Filter
on 23.8. 2011 31x180 seconds M71
on 26.8. 2011 135x90 seconds Garrad mit M71
After trying all kinds of stacking of the comet (stars were reduced with morphology) in PI i ended up using a simple average.
All kind of sigma clipping reduced the tail of the comet to much.
The comet alone looked like that:
http://www.werbeagentur.org/oldwexi/gallery_deepsky/Garrad_M71_man_cometonly.jpgThe final result was not an easy task - took me 5 days, i hope PI will offer in the later future a solution
which allows a "computerized automatic" stacking on a large number of comet images centered on the comet...
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Aloha
Gerald
