Sharpless 115 (SH2-115)

[steppenwolf]

SH2-115

Introduction

Having successfully captured a detailed colour image of SH2-112, I wanted to try its near neighbour SH2-115 but this object is much dimmer and it has proved to be quite difficult to capture any deep data. However, it is also an object that proves the old adage ‘there’s no substitute for lots of subs’!! Current poor skies have hampered this endeavour but over four nights of cloud-dodging between 12th and 17th September I managed to collect 17.5 hours of Ha data to produce this mono image. Unusually, I had to process the data in two totally different ways to achieve the result that I wanted and this is the version that I have settled on.

Description

SH2-115 is located about 7,500 light years away in the constellation of Cygnus about 2° north-west of mag. +1.25 Deneb. The emissions that allow us to observe this beautiful nebula are driven by the energy from a cluster of stars known as Berkeley 90 whose stellar winds are responsible for sculpting away much of the original dust that originally inhabited this region.

Image Stats

Mount: Mesu 200
Telescope: Sky-Watcher Esprit 150
Flattener: Sky-Watcher Esprit specific
Camera: QSI 683 WSG-8
Filters: Astrodon 3nm Ha
Subframes: 35 x 1800 sec Ha
Total Integration: 17.5 hours
Control: CCD Commander
Capture: MaxIm DL
Calibration, Stacking and Deconvolution: PixInsight
Post-Processing: PhotoShop PS3

Location

Constellation	Cygnus
RA	20° 35' 12.0"
DEC	+46° 52' 39.0"
Distance	~7500ly

 

 

[Kinch]

Indeed - even with all that 'activity' it is quite a hard capture - but you have brought it out beautifully. (My effort here: https://www.kinchastro.com/sh2-115.html....if you are interested)

[andrew s]

There have been some cracking images posted lately and here is another.

Regards Andrew 

[andrew s]

1 minute ago, Kinch said:

Indeed - even with all that 'activity' it is quite a hard capture - but you have brought it out beautifully. (My effort here: https://www.kinchastro.com/sh2-115.html....if you are interested)

Top image too. Is that a PN bottom left?

Regards Andrew 

[Kinch]

2 minutes ago, andrew s said:

Is that a PN bottom left?

No....:  The small blue object, is Abell 71. The nebula is also cataloged as PK 085+04.1, PN G084.9+04.4 and Sh 2-116. Initially cataloged as a planetary nebula, the object is now recognized as a small patch of HII emission.

[steppenwolf]

27 minutes ago, Kinch said:

Indeed - even with all that 'activity' it is quite a hard capture - but you have brought it out beautifully. (My effort here: https://www.kinchastro.com/sh2-115.html....if you are interested)

A very nice wide field image, thank you for linking to it. I like your mono version as well.

[Kinch]

8 minutes ago, steppenwolf said:

A very nice wide field image, thank you for linking to it. I like your mono version as well.

As above - you have some lovely detail which really stands out in the mono image 👍..... NICE!

[peter shah]

astonishing detail....just lovely work

[carastro]

I will attest to the difficulty in capturing this target having tried it twice in the last year.  It is very faint.

You have captured some really good detail in this, dare I ask if you are planning to get colour as well?

Carole 

[steppenwolf]

14 hours ago, andrew s said:

There have been some cracking images posted lately and here is another.

Thank you, Andrew, I'm pleased you like the image.

2 hours ago, peter shah said:

astonishing detail....just lovely work

Thank you, Peter - this was a bit of a nightmare to both capture (because of the sky conditions) and to process because it is so relatively dim!

1 hour ago, carastro said:

You have captured some really good detail in this, dare I ask if you are planning to get colour as well?

Thank you, Carole, judging by the rather poor OIII that I captured last night (albeit in pretty poor transparency!) I might just quit this object while I am ahead and leave it as a mono as I feel that this shows what I wanted to see. My wife will be disappointed though as if it isn't colour, she loses interest!!

[tony210]

Great image Steve and I like it in monochrome.

Tony.

[steppenwolf]

20 hours ago, tony210 said:

Great image Steve and I like it in monochrome.

Thanks, Tony - I am a great fan of mono for both astro and normal photography.

[ollypenrice]

That's absolutely gorgeous: the texture of the surface is tangible, making you want to run your hand over it! 

Olly

[callisto]

I love mono images, specially this one 

 

Mark

[steppenwolf]

17 hours ago, ollypenrice said:

That's absolutely gorgeous: the texture of the surface is tangible, making you want to run your hand over it! 

Thanks, Olly - now there's a thought for a new technology - 'Feelyvision'

17 hours ago, callisto said:

I love mono images, specially this one 

Thank you, Mark, pleased you like it.

[david_taurus83]

Lovely image! Do you get many satellite trails in half hour subs?

[steppenwolf]

3 hours ago, david_taurus83 said:

Lovely image! Do you get many satellite trails in half hour subs?

Thank you, David - I have just done a 'blink test' for you on the 35 images that I used for this image and only one of them has a satellite trail. I also have a 'rejects' folder for this project and this contains 4 subframes, none of which have a satellite trail but one of them does have a VERY bright aircraft trail through it which is why it is in the 'reject' folder (see image below)! However, some nights I do get some trails but as I dither all my images and use a stacking routine that removes all the more outlier pixels, these are normally completely absent from my finished image. I certainly wouldn't be put off capturing deep exposures like this because of the risk of satellite trails.