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How to combine LRGB with HaO3 data for NGC 7662 processing

Acquisition HDR Processing H-alpha LRGB OIII Planetary Nebula
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Michael J. Mangieri avatar
Michael J. Mangieri avatar

I am in the process of processing my Blue Snowball (NGC 7662) data with PixInsight. I have L,R,G,B, Ha and O3 subs. Since the object is fairly bright, I was going to do some HDRMT treatment of the HaO3 data to bring out the details. I generally have quite a bit experience in post processing most combinations of filter data, but this one has me a little stumped.

My question is this (sorry if I’m not fully explaining myself, but here goes):

How do I end up with an LRGBHaO3 final image? I made a reasonable LRGB image and a starless HaO3 (with subsequent HDRMT applied) image. But how should I combine the two? I usually do LRGBHa and there is a script for that.

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Armin Lukas avatar
Armin Lukas avatar

Have you tried the CombineRGBAndNarrowband script? (Pixinsight: Script/Toolbox)

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James avatar
James avatar

I’ll be interested to see how others tackle this but my latest image is exactly this scenario. Planetary nebula data (NGC 1360 in my case) with broad band stuff, like a galaxy in the frame.

I processed the narrowband and broadband data separately. Then used photoshop to blend the HOO image with the LRGB image (I believe I used the screen method). I processed the HOO background data to be very dark (but not clipped) since I find the background in the LRGB image more pleasing. I suspect the image blend script in Pixinsight may be able to perform a similar process.

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Stephen Jones avatar
Stephen Jones avatar

Im no guru. Why not create a Hoo pallet with your Ha and Oiii using pixmath

0.6*Ha + 0.4*Oiii and change the amounts making sure they =10. Then combine using imageblend

You could use Bills scriplets as well. Or continuum extraction from Ha and add to Oiii.

Michael J. Mangieri avatar
Michael J. Mangieri avatar

I started with the HOO and LRGB with image blend but the core of the PN is blown out. I’m struggling with getting the detail to show (that is there) using some hdr processing but results haven’t been good yet. Still experimenting. Thanks for the suggestions.

Tobiasz avatar
Tobiasz avatar

Armin Lukas · Jan 1, 2026, 11:17 PM

Have you tried the CombineRGBAndNarrowband script? (Pixinsight: Script/Toolbox)

Exactly this. It works very well.