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.



Eastern Veil - NB Tricolour

Recommended Posts

We were quite pleased with our snap of the Bat Nebula https://stargazerslounge.com/topic/280222-bat-nebula-eastern-veil-bicolour/ until, that is, we saw this masterpiece from Bill Snyder http://billsnyderastrophotography.com/wp-content/uploads/2013/11/Eastern-Veil-CFHT-Ha-OIII-SII-PS1-V4-CR.jpg

Mr Snyder had used all three NB filters, but it was not at all clear to us how he achieved the final result.  We captured a couple of SII frames and tried doing multiple different combinations and blends but got nowhere near.  So eventually @MrsGnomus  e-mailed Bill.  He got back to her fairly quickly and said that he started off with a reasonably conventional SHO (Hubble) mix.  He then started by following Bob Franke's method -  http://www.bf-astro.com/hubbleP.htm 

I got the SII - last night with a ludicrously bright 'supermoon' looking on.  It was noticeable just how much brighter our 'black' level was with the moon around even with the 3nm Astrodon filter.  Also the Veil is really getting a bit too low in the sky I think.  All told we got around 3 hours of SII last night to go with the 5 hours of Ha and 3 hours 40 mins of OIII.  I did a SHO combination - followed by the Franke method and then I got decidedly trigger-happy with the Selective Colour tool in PS.  I don't think I would be able to reproduce what I did.  I didn't get anywhere near the Snyder image, but the result was 'interesting'.  Our bicolour shot is better.  Nevertheless, I might try to get some better SII next year when conditions are more favourable.  

The main lesson we learned was not to try imaging during a near full moon even with 3nm filters.  (We simultaneously tried getting some 3nm OIII through our widefield rig - the individual subs looked OK but once processed, it was clear that there was a massive gradient running across the frame which DBE only partially eliminated.)


Comments and criticism welcomed as always - this is certainly more of a work-in-progress than a finished effort ....

  • Like 9

Share this post

Link to post
Share on other sites

To be honest I have a bicolour version of this, and then recently I finally acquired some Sii to go with it.  When I put it together I did not like the result as much as the bicolour version, so I scrapped it. 

I think in your case too I prefer the bicolour version, somehow the Sii seems to make it less striking in both our images. 




  • Like 1

Share this post

Link to post
Share on other sites

Hi Steve

So far I am with Carole the bicolour version was top drawer, SII has killed some of that lovely smoothness and detail you managed.  Maybe just a case of waiting for better SII.

Have you tried blending in PI?  I would start with -   R=s*.76+h*.24, G=h*.85+s*.15, B=Ox1.0 - Then SCNR (adjust SCNR to taste)

See what that looks like - I hope to have a go at part of the Veil my self shortly - no evidence the above will work, it just does when i try on most NB targets (can always tweak ratios a little if desired).  Unlike any PS method PI seems to blend it 'better' (that's today's technical reference covered :) )  




Share this post

Link to post
Share on other sites

I will try to 'Blend it like Gilliland'.  Let you know how I get on.

Share this post

Link to post
Share on other sites

Interesting point - I have all three sets of NB data ready to process in PixInsight but my previous efforts with the Veil (with Photoshop) showed a similar dilemma.  The SII just didn't improve it.  I have lots of data to process and an enormous amount to learn as I get to grips with PI !!

Share this post

Link to post
Share on other sites

If you already have the 3nm HII filter, then maybe give the [NII] a go as well. On the occasions I've tried I've seen more [NII] than [SII]. In fact, although I'm not sure I have the sub, when I was looking at the Eastern Veil last I tried a [NII] image and saw quite a bit of signal. Unfortunately the sky clouded over before I could do a proper run and I never got back to it as my house was getting in the way.

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.

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.

  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • By knobby
      Hi all, my second attempt at imaging over multiple nights, captured 60 mins Ha and a couple of 5 mins on Oiii and Sii on Christmas evening, then added more Oii and Sii on the 30th
      Total of 60 mins Ha 25 mins Sii and 30 mins Oiii
      Hubble mapped - SII,Ha,OIII = R,G,B. The Oiii data was very noisy but I'm fairly happy overall, also the ZWO Oiii filter caused a massive ring around Alnitak when stretched !
      Comments welcome, I know it needs more data and I will need to learn to be more patient but the year is running out  🙂
      Thanks for looking and have a good 2020.

    • By mikemabel
      These are my last images of 2019 taken with my ED72 and 183mm pro to be replaced by a 533pro
      These targets are not easy due to location trees etc except M1 , there was a bright moon as well so are all lucky shots
      but at last i have taken them warts and all . My guiding was all off as well
      Anyway a merry Christmas to you all and a Happy new year 

    • By codeman
      IC4604 in LRGB Filters. Taking for Namibia during my visit in June 2019. This beautiful nebula is part of the rho Ophiuchi colorful cloud, i the center a 3 blue bright stars the reflect the blue light on the nebula.
      Photo Details:
      Lum - 20 x 5min = 100min
      RGB - 5x5min for each channel at BIN2, 75min
      Total Exposure: 175Min (~3 Hours)
      Telescope: ASA 12'' F3.6
      Mount: DDM 85 Unguided
      Camera: FLI 16200 Mono
      Filters: Astrodon
      Thanks for watching,
      My Flicker Page: https://www.flickr.com/photos/101543943@N04/


    • By mikemabel
      My first image of M76 A bit rushed as clear nights are a rarity now
      30x120s Bin 2 Luminance ,SW 102 , ZWO 183MM Pro , OVL field flattener ,guided , processed in Gimp
      Took some Ha as well but poor results for some reason
      Seems an Oiii filter may have brought out some more detail
      i know its not great but just chuffed to have imaged it

  • Create New...

Important Information

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