M13 - 24 May 2011

[MarkS]

M13 from last night - a very quick pre-process - complete with satellite trails.

Modified Canon 350D on Tak Epsilon 180ED with IR/UV filter.
30 x 5min at ISO 800
10 x 150sec at ISO 100



Full version is here:  http://www.markshelley.co.uk/Astronomy/2011/m13_24052011_full.jpg
I fell asleep during acquisition and forgot to refocus with the falling ambient temperature - hence the squiffy stars on the right hand side of the full image.

Mark

[Rocket Pooch]

Thats very nice.

[JohnP]

That is looking good again Mark & great colours as well. Ton's of background fuzzies as well... Can't believe you have so many satellite trails....?

John

[RobertM]

That's a really impressive result Mark.  I love the star colours.

[The Thing]

Fantastic. Shows how important the scope is. No substitute for good optics.

[MarkS]

Fantastic. Shows how important the scope is. No substitute for good optics.

Indeed, for full colour imaging you can't beat fast optics and dark skies.

[mickw]

Great image but why are you getting 6 point spikes at the bottom of the large version ?

[MarkS]

Great image but why are you getting 6 point spikes at the bottom of the large version ?

When the DSLR mirror folds away during the exposure, it still sticks out far enough to interrupt the lightpath to that part of the CCD at a fast F-ratio of F2.8

A straight edge interrupting a lightpath causes a diffraction spike at right angles to the straight edge.

[The Thing]

Fold it away - permanently

[mickw]

That's a bummer, only affects the bottom though luckily 

[Mac]

Stonking image.

Mac.

[MarkS]

I have thought about removing the mirror entirely but I don't know of anyone who has tried it and I don't want to risk any unintended consequences.

[PhilB]

I'd have to rate this image as the best M13 I can remember seeing!

[Carole]

Amazing resolution, love those star colours.

Carole

[Fay]

that really is great Mark!!!!!!