ngc3372 Carina nebula

[sgazer]

hi,

this is my first real go at deep sky imaging for about a year since moving out to Oz, so I'm a bit rusty and this is my first go at Ha imaging. I'm about 10 miles from Melbourne city centre and there's lots of street lights around and a flood lit company premises near my house, so the Ha filter works wonders, keeping the back ground nice and dark.

Here is the Carina Nebula. 32x3min subs with darks. 7nm Ha filter. Stacked in DSS, levels and curves in PS, noise removal with Neat image. I'm wondering if the noise removal has made it a bit soft, but think it gives it some depth.

[carldr]

I agree, that has some nice depth to it. Was that taken with your 150P and Canon 1000D?

[sgazer]

thanks, yes it was with the 150p and 1000D.

I want to use Iris at some point to extract the red channel only out of the raw image to reduce the noise contributed by the other channels, but it take a while to do manually and I'm not sure of the results.

[carldr]

That's impressive for a DSLR (even if it has been modded) and only 90-odd minutes of exposure.

[Dann]

Thats a great picture, love it!

[Telrad]

sgazer, beautiful image with great resolution of the Carina Nebula. I like the reddish colour contrast against that inky black. It looks wonderful, and certainly has plenty of depth and detail. Well done!

[sgazer]

thanks all for your kind comments. I just ran the subs through Iris to split out the red channels from the lights and darks using the split CFA command. It produces 4 files for each, 1 red, 1 blue and 2 green as per the bayer matix and the resulting files are 1/4 the pixels of the original, so I think it is extracting the raw pixels of each colour. As expected with a Ha filter, there wasn't much in the blue or green, so I just stacked the red lights with the red darks and here's the result. First in monochrome and next with false Ha red. It's the first time I've tried this technique and the images were much cleaner so I didn't have to use any noise filter this time.

[MartinB]

Lovely 3D effect. An excellent return to imaging

[AndyUK]

I love seeing images of Eta Carinae and the Carina Nebula... Like so many other Southern night sky objects, I just wish we could see them on our side of the world.

Can I ask how this compares in the night sky with views of the Orion Nebula...? From what I've read, it's about 4 times the size and also signficantly brighter...

[sgazer]

I love seeing images of Eta Carinae and the Carina Nebula... Like so many other Southern night sky objects, I just wish we could see them on our side of the world.

Can I ask how this compares in the night sky with views of the Orion Nebula...? From what I've read, it's about 4 times the size and also signficantly brighter...

yeah, I'm slowly learning the new objects down here, there are quite a few large bright beauties. TBH, I couldn't see the nebula or the main star, Eta Carina, which I believe is 100 times bigger, 1 million times brighter than our sun and is approaching the theoretical maximum for the size of a star.

[sgazer]

ps, amazingly another clear night tonight, so I'm capturing OIII and Lum subs as we speak. I've not done a narrowband combined image before, but I'm planning to generate a false green channel with Noels actions and go from there.

I'm noticing a lot more detail in the inner regions with the lum subs (UHC filter), but not so much of the outer regions. The OIII was quite feint.

[AndyUK]

Can't wait to see the result! Interestingly I've just done my first narrowband image as well... (and the OIII signal (from NGC6888) was pretty tiny too).

[sgazer]

Can't wait to see the result! Interestingly I've just done my first narrowband image as well... (and the OIII signal (from NGC6888) was pretty tiny too).

are you going to create a false green channel too? Did you do some luminance subs? I'm not sure how to tie the lum in with the RGB image, but I think there are some tutorials around somewhere

[AndyUK]

Ah.... I'm afraid I cheated - I made mine an HOO image, as apparently that gives quite a reasonable result with NGC6888. It's still WIP as I'm hoping to get another 4 hours of OIII to see if I can get some better detail on the outer shell. So far I have 37x10 Ha and 27x10 OIII...

I did find this link for NGC3372 as a guide though, which uses Ha as a luminance layer and then assigns the RGB channels to the 3 narrowband filters. The first version is an HOO (with H luminance) if you didn't want to go quite as far as using all 3 filters. The guy who captured these took 23x20 SII for his HST Pallette version, but I'm quite surprised how few Ha (4x20) and OIII (6x15) were used for the first image... (Good result...!)

[sgazer]

that's great thanks. I'm still working on mine too, it's tricky getting a combined image looking better than the original narrow bands or lum!

[AndyUK]

it's tricky getting a combined image looking better than the original narrow bands or lum!

How true...! Not being at all used to mono, I'm finding it's really tricky knowing what the impact on the end result is going to be when making adjustments on one filter/channel...

[NickK]

Little saturation on the stars but the depth of the red is really nice.

[Coco]

Love these Southern targets, thanks for posting, look forward to seeing more from the south..