Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

Sign in to follow this  
Hallingskies

Yet another M42...

Recommended Posts

Not that anyone could get fed up with this object...

M42-6.jpg

Date: 01 January 2018

Equipment: SXV-H9, Vixen 114mm f5.3 ED refractor, guiding with Lodestar X2/PHD

Subframes: 30 x 300s, 100s & 20s H-alpha, 20 x 20s & 100s RGB 2x2 binned, 20 flats for each channel, no darks (hot pixel removal in Astroart instead).

Images were acquired and pre-processed (aligned, stacked, denoised) in AstroArt4, then composited in Paint Shop Pro7.

The Orion Nebula presents quite a challenge to depict because of the wide brightness range of its key features. Many early CCD images of this object as shown on the web "burn out" the "trapezium" region of the four central stars in attempting to show the outlying nebulosity.

I use the "layers" function in PaintShop Pro, stacking the longest exposures on top of shorter ones, and then carefully use the "eraser" tool to remove overexposed areas, leaving the underlying correctly exposed regions to show through. This has to be done with care to avoid introducing obvious processing artefacts.

Whilst the latest image processing programs such as Pixinsight have "dynamic range adjustment" features that can automatically produce an even distribution of brightness, some of the resultant images can seem rather strange to my eyes. Programmes like that are way beyond both my budget and my understanding!

LRGB combination (using the H-alpha stack as the luminance channel) went well in both Astroart and PaintShop Pro. The PSP version was a lot greener than the Astroart one (though you can “weight” colours to compensate for CCD sensitivity at different wavelengths), but I preferred the PSP output as it hinted at the greenish hue of the nebula that is so clearly discernible though the eyepiece.

All of the brighter features seen in the above image show clearly through my VC200L and a 25mm eyepiece. The central trapezium of four stars shines brilliantly against a bright silvery background, which fades into the convoluted greenish wings of the surrounding nebula. The dark channel between the main portion of the nebula and the upper candle-flame is clearly seen.

I strove to retain all of these key features in the image above, as well as highlight the extended nebulosity that the eye cannot see.

Any comments, criticisms or suggestions gratefully received...

  • Like 5
  • Thanks 1

Share this post


Link to post
Share on other sites

and yet, another beauty.

I too manually mask out the blown out areas...

 

 

Share this post


Link to post
Share on other sites

Nice image. Looks like you've managed to tame the noise with that smooth but detailed nebulosity.

Cheers, Ian

Share this post


Link to post
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
Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • By Nicola Hannah Butterfield
      First image from my new NEQ6 Pro driven mount, all other images before this were static.
      Sky Watcher 200P prime focus, 10x 60's lights, darks, bias and flats. ISO 200
      Bortle 6
      Yes I know there is a plane track through it.
    • By alexbb
      I've been processing this image for quite a long now.
      I started acquiring data the last season when I only managed to shoot 3 panels with the Canon 6D through the Esprit 80 for a total of ~7h.
      This season I restarted and I added more data and covered a wider area. So a mix of portrait and landscape panels were planned and shot with the same scope and camera. Now every pixel represents at least 3-4h of integration, some have more.
      All the above were shot from Bortle 2-3 sites where I traveled sometimes even for an hour of exposure.
      To the RGB data I added 17.5h of Ha, same story with the panels. Some were oriented N-S, others E-W. These were shot with the SW 72ED and the ASI1600 from home and Bortle ~7.
      Then I figured out I still had time and I planned and shot 9 more panels of luminance with the 72ED and ASI1600, each consisting of 1h of exposure.
      I combined all of these into an image, processed it and for the Orion nebula and Running Man nebula I also blended some data I shot last season with the 130PDS and ASI1600 from home.
      Below it's my first final version of all data combined. You can watch it in full resolution on astrobin: https://www.astrobin.com/full/jni0w8/ or Flickr: https://flic.kr/p/2iBGUXq
       

    • By MarsG76
      The Orion Nebula imaged in RGB through a Celestron 8" SCT at F10 (2032mm FL) using a full spectrum modded and cooled Canon 40D. Tracked using a Celestron CGEM mount. Total exposure time was 1 hour and 24 minutes.
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.