Jump to content

Banner.jpg.b83b14cd4142fe10848741bb2a14c66b.jpg

Heart Nebula in Hubble Palette (Ha & OIII) with a Nikon D5300


Xiga

Recommended Posts

We had a patch of clear skies last Sunday night, and even though it was bitterly cold (and there was ice and snow everywhere) I made the executive decision to get outside and have a go nonetheless. I have to setup and teardown each session, but thankfully I was able to move the car a few metres and take advantage of the nice dry (and ice free) ground underneath.

The plan was to grab some OIII data to go with the Ha I captured on the Heart Nebula a couple of weeks back (see link below) but all I could manage was 8 x 1200s before the clouds rolled in for good. In fact, 3 of the 8 subs were affected by clouds, but I decided to use them anyway as I figured it’s only going to get used for tone mapping, and not luminosity, and at such a short exposure time I really need all the SNR I can get. So I’m being a bit of a naughty boy by posting this before getting a decent amount of OIII first.

This is just a quick once-through process and is still missing some things, so it’s very much a work-in-progress at this stage, but I thought I’d post it anyway and I’ll update the thread as I make changes. So far, all I’ve done is process the OIII image (which involved gradient reduction, stretching, removing the stars then stretching some more, then quite a substantial amount of noise reduction). Then I combined it with the Ha image above in my usual manner, i.e creating a synthetic SII using 60% of the Ha image and 40% of the OIII image, and then combining all 3 using Annie’s Hubble Palette action.

So aside from some more work to refine the colour, I still need to work on the contrast, do some NR and also then finally some star reduction.

C&C welcome as always!

Details:

SW 80ED with FF/FR (510mm FL)
HEQ5 Pro Mount (belt mod)
Nikon D5300a
11 x 1200s and 3 x 900s of Ha (2” Baader)
8 x 1200s of OIII (2” Baader)
30 Flats, 50 Bias. Dithered every frame.
Captured in SGP. Stacked in APP. Processed in PS.

Thanks for looking.

 

The Ha image:

 

Heart Nebula HST Image v1.jpg

Link to comment
Share on other sites

Thanks for all the comments peeps :smiley:

I didn't have much time tonight to make many improvements, but i did realise that using a blend of 80% Ha and 20% OIII for the synthetic SII gives a much better starting position for the colour. It was then that i realised that i'd gone waaaaay over the top with the blue in the first version above. 

So here's one with, hopefully, something closer to what the colours will look like in the final version. Now just have to get around to doing all the remaining adjustments.

 

1. Heart Nebula HST Image v2.jpg

Link to comment
Share on other sites

31 minutes ago, Adam J said:

I am surprised at how much OIII you managed to get in the heart I found it to be very dim when I did the soul. Maybe slightly more in the Heart??

Can you show the OIII data on its own?

I was surprised too Adam. Especially considering the relatively short total exposure time. The only thing I can surmise is that the Heart must contain quite a bit more OIII than the Soul. For comparison, when I shot the Elephant Trunk recently, I captured a good bit more OIII than I did here, but it didn't end up looking like that much more (indeed possibly even less) after I'd processed it. I also think the Sony sensor in the 5300 plays a big part too. It consistently impresses me the more I use the camera.

I'm at work right now, but later tonight i'll post jpg's of the raw OIII stack and also the heavily-processed starless version I used when combining. I think you'll be surprised at how far you can push the OIII, on it's own it looks absolutely terrible!

ps - I've asked Santa for a copy of The Astrophotography Atlas for Christmas. I think it will give details on what each object is made up of, which should hopefully make planning future targets all the more easy (once I get all the big hitters out of the way first).

Link to comment
Share on other sites

15 hours ago, tooth_dr said:

Much better.  I started imaging this on Wed night, looking at yours I think my framing may have just missed the phalic appendage :D

Lol, i know what you mean Adam. It does have a rather, erm, unfortunate shape, lol. I just know when i finish it and show it to my mates it will be the first thing they say! :tongue:

Looking forward to your version. Were you shooting Ha or OIII?

Link to comment
Share on other sites

13 hours ago, Adam J said:

I am surprised at how much OIII you managed to get in the heart I found it to be very dim when I did the soul. Maybe slightly more in the Heart??

Can you show the OIII data on its own?

Ok Adam i've attatched below what the OIII stack looked like after nothing but a basic auto-DDP stretch from APP. So as you can see, still very little nebulosity showing, but i've certainly seen a lot worse on other objects. 

And the 2nd image is the one i've actually used when creating the Hubble Palette image. As you can see, i've removed the stars, given it an almighty stretch, and then really gone to town on the noise reduction. Amazingly, the roughness doesn't really show up in the final image, at least not in a manner that you would expect, and it seems to be worth it to be able to get a much more aggressive stretch out of it. I think in the end, the only thing that matters is that as long as you remove the stars and use it just for tone mapping only, then as long as the patches of nebulosity and sky background are relatively smooth, then the rest of the warts don't really matter so much. 

OIII stack.jpg

2. Starless stretch NR.jpg

Link to comment
Share on other sites

Ok, i did some contrast enhancement (i went subtle on this, i'm always cautious to overdo this part, especially late at night when the brain & eyes aren't working at their best!), and also reduced the stars and applied a subtle amount of NR. 

I noticed i ended up with yellow stars this time instead of magenta ones. I think this was down to the fact that i used a starless OIII layer rather than one with stars. I don't mind them, so i think i'll leave them as they are and not bother working to change them to white. No HDR toning done this time, i felt it created an image that looked a bit too over-processed to my eyes. 

Thoughts welcome as always! 

 

 

Heart Nebula HST Image v3.jpg

Link to comment
Share on other sites

17 hours ago, MartinB said:

Outstanding work Claran.  Your commitment and attention to the details of all stages of the imaging process is really delivering results.

Thank Martin for your kind words! :happy7:

I usually like to post a starless version of my images as well, as i find them quite striking. And it's just a bit of fun too :tongue:

Heart Neb HST Image Starless.jpg

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.