Dumbbell Nebula - super resolution HaRGB

[gorann]

The Liverpool Telescope is a 2 m f/10 RC scope on La Palma, Canary Islands, that gives away their subs for free once the astronomers are done with them. A great way of keeping up the processing skills for Swedes while waiting for dark nights to come back in September.

Of all the Liverpool Telescope data I have processed, this was possibly the best, and I think the final result shows some stunning detail in this nebula. In my humble opinion it is as good as, or maybe even better, than images I have seen from much larger scopes, including the 8.2 m Subaru Telescope (Hubble has only imaged a small detail of it).

For this image I used subs from five filters (60, 90 and 120 s exposures, average ca 90 s) taken during 2015-2016. After throwing out subs with eggy stars or poor focus (about 30% of my downloads - LT appears to save everything), I ended up with these:

sdss-r 38 x 90 s (red data)

Ha 15 x 90 s (33 % mixed with 67 % sdss-r for the red channel)

Bessell B 43 x 90 s (mainly blue data)

sdss-g 20 x 90 s (mainly blue data, 33 % mixed with Bessell-B for the blue channel)

Bessell V 33 x 90 s (used for the green channel)

So totally 149 x 90 s or 3.7 hours

The camera is a 6 x 6 cm (15 µm pixels) 18 Mpix CCD camera (2x2 bin) of the brand e2v, which I think is chilled to -100°C.

Stacking in Nebulosity 4 and processing in PS CS5. The data was so clean that I did not apply any noise reduction but I did some very mild sharpening (deconvolution) using the Focus Magic filter for PS.

For comparison. here is an image largely based on data from the 8.2 m Subaru scope. It is in general strikingly similar to my LT image (but I actually did not find it until afterwards - so not used for inspiration):

http://www.robgendlerastropics.com/M27-Subaru-HST-BYU-FR.html

Most images I have found of it on the net are NB images. Here is Bill Snyder's Ha-OIII version of it:

http://billsnyderastrophotography.com/?page_id=1767

 

Any comments and suggestions most welcome, and for once I also invite pixel peepers!

[gnomus]

Hey Goran ...  Surely you could get just a bit more colour into that image!!!

[gorann]

Just now, gnomus said:

Hey Goran ...  Surely you could get just a bit more colour into that image!!!

Steve, I could easily crank up the saturation a bit, but maybe you are trying to say I should do the opposite..... There is a lot of blue data in there

[gnomus]

No - it is a terrific image Goran.  Excuse my attempt to be humorous.  Nice rich colours.  I wouldn't change anything.

[carastro]

Oh Wow, not seen one as close up as that before.  Great work.

Carole 

[gorann]

1 minute ago, gnomus said:

No - it is a terrific image Goran.  Excuse my attempt to be humorous.  Nice rich colours.  I wouldn't change anything.

Thanks Steve!

I feel got slightly "colour blind" after working on it for two days, and worried it was too blue and the red looked rusty. Actually, maybe it looks a bit rusty....

[gorann]

3 minutes ago, carastro said:

Oh Wow, not seen one as close up as that before.  Great work.

Carole 

Thanks Carole!

Now when the nights are getting shorter and lighter even in London, and sometimes even cloudy, maybe you should go for a fishing trip in the LT treasure chest?

[PatrickGilliland]

Nice work - colours are not a problem  the structural details are great.

[wimvb]

1 hour ago, PatrickGilliland said:

Nice work - colours are not a problem  the structural details are great.

Having 0.3 "/pixel at 2 m aperture and 20 m fl on a mountain top in the middle of the atlantic helps.

Great image, Göran. I like the colours.

[gorann]

1 hour ago, PatrickGilliland said:

Nice work - colours are not a problem  the structural details are great.

Thanks Paddy! Much appreciated

Now I can feel good about the colours (and obviously I like them or I would have tuned down the saturation). Most other versions I have seen are quite colourful, so this is either a very colourful object or it inspires us to boost the colours.

Interestingly, there is a significant variation between various versions out there in the misty blue parts, which varies from blue to violet to cyan to green. My version started off quite blue so I kept it that way.

[gorann]

11 minutes ago, wimvb said:

Having 0.3 "/pixel at 2 m aperture and 20 m fl on a mountain top in the middle of the atlantic helps.

Great image, Göran. I like the colours.

Thanks Wim!

There is another one on another mountain top in the middle of another ocean, which has a 8.2 m aperture. I just applied for a password for the Subaru scope's database.......

[wimvb]

So, by the end of the summer you'll be turning out Gendler quality hybrids .

I will stick to the LT for a while, the archives hold enough information to keep me busy for a few months.

[ollypenrice]

Love it.

Olly

[gorann]

1 hour ago, ollypenrice said:

Love it.

Olly

Thanks Olly!