Messier 2 - Take Two

[PhotoGav]

Last year I imaged the globular cluster, Messier 2, in Aquarius... here's the thread:

However, I was never happy with the star shapes in that image, which seemed to be far too Pacman-esque for my liking. I put it down to the low altitude of the target or poor PA or bad weather or just grumpy Sky Gods. Anyway, I decided to revisit M2 as it returned to the night sky this year. Here is my resultant version 2 image:

Technical Details:

Celestron EdgeHD 800, QSI 683-WSG8 with Baader 1.25" filters, HEQ5 Pro

RGB = 19 x 600s each
L = 16 x 600s
TOTAL = 12 hours 10 minutes

I am most definitely happier with the star shapes in this version. I discovered that autofocus was struggling with this target in SGP. Everything appeared to be working fine, but it would get to a point when it would detect the core of the globular as a very large out of focus star, thereby knocking the V curves completely off. So, version 1 had dodgy star shapes because of poor focus, that's all. My solution in this new version was to use a semi-automatic focus routine. When the system needed focusing I would pause everything, slew the scope to a patch of sky slightly away from the globular cluster itself (set up in SGP with the Target and Focus Position Module), run autofocus, centre up back on the globular and then carry on the sequence. This was a very laborious technique, which required me to nurse the whole thing each night, rather than the effortless position I have been in of pressing start and retiring to bed for a good night's kip only to find a folder full of subs on the obsy PC in the morning! But it worked and I managed good, sharp (well, sharp for the Edge 8" anyway) data.

The other point of interest with this project is that it was almost entirely shot remotely. I was on a two week family holiday in Southern Italy throughout the last New Moon. So, I connected my laptop to my phone hotspot, logged in to my observatory PC and controlled the whole operation from the veranda of my house in Calabria! It was quite a relief when the shutter actually closed at the end of each session - not sure what I would have done if there had been any hardware issues back home! The irony is that I had always thought how great the house and night sky in Italy would have been and I should set up an observatory there to remote control from Wiltshire. It has ended up being the observatory in Wiltshire that I have operated by remote control from Italy!!

Anyway, I hope you like the version 2 image of this glorious globular.

Clear skies all!

[Davey-T]

Lovely image Gav, nicely resolved stars.

Dave

[Petergoodhew]

Nice detail right to the core.

[Knighty2112]

Excellent image. Well worth the revisit!  

[bingevader]

Very sparkly, well done.

[PhotoGav]

Thank you for the positive feedback Dave, Peter, Gus & Ben. I agree, it is rather sparkly!!

[Mark at Beaufort]

Very nice image Gav. I always enjoy observing M2 - thanks for the post update.

[PhotoGav]

Thank you Mark. M2 is a glob I’ve never observed visually. I’m hoping that will change tonight. The forecast is for a clear patch and M2 is top of my list!

[swag72]

That's looking really good Gav...... love it!! 

[PhotoGav]

Thank you Sara.