M27 Dumbbell

[drjolo]

M27 is a kind of special target for me - it was the first deep sky object I imaged several years ago with digital sensor. Since then I have been imaging Dumbbell each time I upgraded my setup with something new. I purchased my current scope over half year ago, but this time I needed to wait till M27 will move higher in the sky. And over several nights  in July/August this year I collected subframes to the image below. It is HaORGB composition made with Meade ACF10" telescope and QHY163M camera on EQ6 mount. Ha 100x5 minutes, Oiii 30x5 minutes, RGB 50:30:40 x 30 seconds. 

Thanks for watching!

[alexbb]

You have a really excellent resolution! I wonder if you could still stretch the data a bit more to reveal more the outer nebula. I expect you should have a fair amount of clean data close to the background level.

[Shibby]

Incredible detail, lovely image! With your current kit working so well, I'm sure it'll be some time before we see the next M27 from you

[coatesg]

That's a super image - the detail in the nebula itself is outstanding! The outer shells would be the icing on the cake for this!

[drjolo]

Thanks! I hoped I collected enough Ha to reveal outer shell - here is how stretched Ha looks like:

So its pretty disappointing  I tried to reduce noise and stretch it further, but then stars at Ha become big and bloated. I suppose there were some high clouds there, and stars have some faint halos. Seeing was pretty good, and FWHM was about 2" in average. I probably miss some processing skills to reveal this halo better. But will work on it  

[alexbb]

1 minute ago, drjolo said:

Thanks! I hoped I collected enough Ha to reveal outer shell - here is how stretched Ha looks like:

So its pretty disappointing  I tried to reduce noise and stretch it further, but then stars at Ha become big and bloated. I suppose there were some high clouds there, and stars have some faint halos. Seeing was pretty good, and FWHM was about 2" in average. I probably miss some processing skills to reveal this halo better. But will work on it  

I would say the Ha looks excellent. But the more visible halo is emitted by the Oxygen. Though, in this new rendition, even the Ha line is more visible than in the initial post, maybe because it's b/w.

On an absolute irrelevant note for the image, I prefer this orientation.

[drjolo]

I found out Ha in mono version is always better defined (at least for me). Once I make Ha red it then becomes pretty faint. 

But thanks for comment - I will take a little break from this image and get back to it  

[kirkster501]

Fantastic! So is the rest of the stuff on your website.

Interesting your RGB subs are so short......???

[ollypenrice]

A lovely unforced M27 with tiny stars.

I don't know how you add Ha but it should be possible to stretch it harder and then star reduce it aggressively so that the Ha stars don't affect the RGB ones at all.

Olly

[drjolo]

4 hours ago, kirkster501 said:

Fantastic! So is the rest of the stuff on your website.

Interesting your RGB subs are so short......???

Thank you! I decided to make them short to minimize tracking errors. And with CMOS camera when you increase gain you do not loose much in terms of read noise.

3 hours ago, ollypenrice said:

A lovely unforced M27 with tiny stars.

I don't know how you add Ha but it should be possible to stretch it harder and then star reduce it aggressively so that the Ha stars don't affect the RGB ones at all.

Thanks. I made at the beginning starless bicolor image (Ha + Oiii) then added RGB stars as another layer. I will try different approach next time.