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Started by RobertM, Apr 12, 2022, 22:13:54

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A recent quickie but I mucked up collimation, hence the stars are very squiffy and it could be better.  Also the flats didn't work very well so I had to resort to the synthetic type (not sure I found the best way yet).

60 x 120s Captured 26/27 March 2022 from Orpington using a Celestron Edge HD11 at f/10 and ASI2600MC Pro camera.

Have wanted to do a bit of galaxy imaging for a while but never really had the telescope for it before.


The Thing

Some good detail in there for 2 hours data. I like the way you've got the dust to pop a bit. Things to check are that the secondary is actually centred as well as collimated. Make yourself a Duncan Mask! (not a mask with my face on that is  :o LOL ). Mark is the expert with these scopes. With my 8" Meade rotating the corrector away from the marked position made a huge difference as well.
Cloudy? ¯\_(ツ)_/¯ (Gallic shrug :))


Thanks Duncan.  The scope is ok.  The collimation problem was down to user error; once set the stars were round but that was after.



very nice.

pity i dont get any time at the moment,



Great image Robert. Detail in the spiral arms is superb.

Clear Skies,



Nice M51 Robert
It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!


What are artificial flats and how do you do them?
Nice image, especially from Orpington and with a slowish scope.



Thank you all.

Carole, in this case the artificial flat was generated by removing celestial objects from the image then the resulting image is subtracted from the original.  It's not quite as simple in practice but that's the theory.