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.

sgl_imaging_challenge_banner_android_vs_ios_winners.thumb.jpg.803608cf7eedd5cfb31eedc3e3f357e9.jpg

Sign in to follow this  
AKB

Eastern Veil with 'Quad-band' filter and ASI294MC

Recommended Posts

I'm still in the process of commissioning my latest imaging rig:

  • Esprit 120ED
  • ASI294MC Pro camera
  • Avalon M-Uno with new Dual mount head

I've also run across two new things recently (new for me, anyway):

I wanted to share the latest results from a combination of all of these.  I didn't think I'd have the chance for a while, what with the weather, but, unexpectedly, I got a window last night and captured 20 x 2 minutes  before the moon came up, on my benchmark target for this sort of thing, the Eastern Veil.  The filter is actually a Dual band filter, but as described on Altair's site:

    "Quad Band - combines Sii AND Ha into a red zone, and H-beta + Oiii into a green/blue zone. (Recommended for moderate light pollution)."

Here are two images:

  1. 20 x 2 minute stack with just an arcsinh stretch plus another histogram stretch after colour calibration and background removal,
  2. starless version of that image straight out of Starnet++

This is definitely the best image I have to date of the Veil.  Not too shoddy for 40 minutes total.  Can't wait to try adding some more time to this... (a long while, though, until I attain the sort of result here)

https://stargazerslounge.com/topic/342730-eastern-and-western-veils-ngc6960-and-ngc6992

Anyway, here we are.  Comments and suggestions welcomed.

Tony

 

20191019_EV-120ED-ASI294-Quadband-20x2m.thumb.jpg.c9073ea367c96dff2810bf6ad4c632a3.jpg

 

20191019_EV-120ED-ASI294-Quadband-Starnet-20x2m.thumb.jpg.18c39e65c891050026234acf8d5581c2.jpg

 

  • Like 11

Share this post


Link to post
Share on other sites

Thanks for the likes.  In the end, of course, a mixture is probably best, with a more conventional red/blue palette (thank you SCNR!)

 

20191019_EV-120ED-ASI294-Quadband-Starnet-Stars-20x2m.thumb.jpg.b6e61829e7329c9952978f64fd1cb0da.jpg

Edited by AKB
  • Like 4

Share this post


Link to post
Share on other sites

Great image Tony, This with the 294 and the Tri-band or Quad-band as they have different red pass band widths?

Might be worth imaging without the narrow band combination filters for star colour (+UV/IR Cut) then over lay the starless NB image - just a thought.

 

  • Thanks 1

Share this post


Link to post
Share on other sites
57 minutes ago, fwm891 said:

This with the 294 and the Tri-band or Quad-band as they have different red pass band widths?

This is the Quad-band. 

I know what you mean about the star colour, but, for me, the whole point of these filters with an OSC is just get away with”one shot.”

Although... perhaps I need a dual rig ...?!

  • Like 1

Share this post


Link to post
Share on other sites

This is really impressive! I can't believe I am faffing around with a DSLR unmodified and imaging for 16 hours to get an image with way less SNR than this. 

I need to buy myself my ASI294MC Pro !

 

  • Thanks 1

Share this post


Link to post
Share on other sites

love these images, just had my first serious go at DSO imaging and it was the same subject. Wish mine looked half as good as this!

How do you remove the stars? The image with them added back in faintly is my favourite, on my image they almost overwhelm the nebula itself.

Thanks
Ed

  • Thanks 1

Share this post


Link to post
Share on other sites
On 24/10/2019 at 22:46, edarter said:

How do you remove the stars?

This is entirely the purpose of Starnet++, which you’ll find discussed in several places here on the forum and you can get from here...

https://sourceforge.net/projects/starnet/

Workflow is essentially

  • calibration and background removal
  • modest stretch with, say, arcsinh stretch
  • Starnet++ to remove stars
  • subtract starless from stretched original to give stars
  • process/stretch each separately to give the result you want
  • combine/merge in some ratio 

I’ve suffered exactly the same issues with the background (or foreground) stars dominatng RGB images, but this processing seems to work very well.  You can find a very good example of this here, on a difficult target with rather poor data, for Ced 201 which I recently reprocessed with the above workflow here (original processing in same gallery.)  

Tony

 

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

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