Orpington Astronomical Society

Astronomy => Astrophotography => Topic started by: RobertM on Apr 12, 2022, 22:13:54

Title: M51
Post by: RobertM on Apr 12, 2022, 22:13:54
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.

Title: Re: M51
Post by: The Thing on Apr 13, 2022, 09:13:09
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.
Title: Re: M51
Post by: RobertM on Apr 13, 2022, 12:46:58
Thanks Duncan.  The scope is ok.  The collimation problem was down to user error; once set the stars were round but that was after.

Title: Re: M51
Post by: Mac on Apr 13, 2022, 13:50:05
very nice.

pity i dont get any time at the moment,

Title: Re: M51
Post by: garrick on Apr 15, 2022, 07:51:29
Great image Robert. Detail in the spiral arms is superb.

Clear Skies,

Title: Re: M51
Post by: Fay on Apr 15, 2022, 16:16:20
Nice M51 Robert
Title: Re: M51
Post by: Carole on Apr 16, 2022, 09:31:22
What are artificial flats and how do you do them?
Nice image, especially from Orpington and with a slowish scope.

Title: Re: M51
Post by: RobertM on Apr 19, 2022, 10:35:07
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.