Ngc2997

[Spookyer (Brett)]

Hi all

My latest shot, NGC2997. Got 24hrs of data used the best 18hrs. LRGB. I got some HA but couldn't blend it effectively so didn't use it in the end.

RC-12 and SBIG STT-8300. Drizzled. Processed in Pixinsight.

Suggest you look at

https://www.flickr.com/gp/148252782@N06/7kdwJ6



Cheers
Brett

[RickS (Rick)]

Nice work, Brett.

For a target with small areas of Ha, a simple technique is to stretch and black clip the Ha master to make a mask. Apply the mask to the colour image and use CurvesTransform to tweak the areas of bright Ha (e.g. boost the red and maybe add a little blue to represent Hbeta.)

Cheers,
Rick.

[Spookyer (Brett)]

thanks Rick I will try that next time. I was using the pixel maths technique where you reduce the filter bandwidth down until the stars start to dissappear. In this one I had to go down from 100 to about 3nm and there were still stars showing. I tried using 5 but when I combined the channel it turned some of the stars red.

[strongmanmike (Michael)]

That's a very good 2997 Brett, nicely done

Some serious exposure too! 18hrs was my record over the past 5 years...until my last image, when I finally cracked the 20hr mark (once again) collecting 22hrs. Luckily I was able to use all but two subs of the three nights worth, so ended up just under 22 hrs in the final image

Mike

[marc4darkskies (Marcus)]

Nice work indeed Brett - well worth the effort you put in with good colour and nice detail!

[RickS (Rick)]

Originally Posted by Spookyer

thanks Rick I will try that next time. I was using the pixel maths technique where you reduce the filter bandwidth down until the stars start to dissappear. In this one I had to go down from 100 to about 3nm and there were still stars showing. I tried using 5 but when I combined the channel it turned some of the stars red.

You can always remove the stars, Brett. There are lots of ways to do this but I like to use PixelMath with a star mask: "iif(star_mask>0.1,0,$T)". You can tweak the 0.1 fudge factor to adjust the size of the holes left where the stars were. A convolution blur afterwards will prevent any hard edges.

[Placidus (Mike and Trish)]

That's excellent, Brett. Lovely image.

[ozstronomer (Geoff)]

Very nice image Brett, well done

Cheers Geoff