Jump to content

290128050_ConstellationBanner.jpg.6eb5d1fe82e0853d4c3b80a745d12d74.jpg

M27 Dumbbell


drjolo
 Share

Recommended Posts

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. 

2018-07-23-M27.jpg

Thanks for watching!

  • Like 20
Link to comment
Share on other sites

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.

Edited by moise212
Link to comment
Share on other sites

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

2018-08-08-M27H.jpg

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 :) 

Edited by drjolo
  • Like 2
Link to comment
Share on other sites

1 minute ago, drjolo said:

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

2018-08-08-M27H.jpg

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.

  • Like 1
Link to comment
Share on other sites

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 :) 

Link to comment
Share on other sites

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. 

  • Like 2
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.