M27 Dumbbell Nebula in narrowband

[menardre]

My first attempt at using ZWO ASI 1600 for narrowband imaging was M27. I picked this since it is large and bright and low in the Eastern sky to start so I do not have to contend with meridian flip. I used 5 inch refractor. I took 37 images 2 minutes LUM, and 17 images 2 minutes Red, Green, Blue, Ha, and Oiii. I then used Images Plus to generate the six masters, then aligned the masters and assigned colors to each master. I used the Hubble Color Palette (Ha green, Oiii blue) for this test. This is a cropped image. I did notice that stars in a couple of areas had a distinctly green tint - which must mean that I am doing something wrong when I align and combine the images. All-in-all I am pleased with my first attempt at narrowband imaging. I have a little work to do to iron out the bugs. It is a lot more complicated than one-shot color, but only way to get decent narrowband images of nebula.

Roger

M27 LRGB-Ha-Oiii Cropped.jpg (567.04 KiB) Viewed 1952 times

[Bruce D]

Incredible detail in the nebula Roger, beautiful! I see red flares.on the stars, all towards 2:00, is it possible the red image was a tiny bit off alignment? But who cares about the stars the nebula looks so good!

[Chuck]

Great job Roger and nice detail in the nebula. I look forward to your future images. Thanks for sharing.

[menardre]

As Bruce pointed out there are red flares. This is also a cropped image so not shown are areas where the star colors are inconsistent. I went back and refined the alignment of the LRBG masters and was able to improve the image - especially the stars. I still have a lot to learn about imaging with a monochrome camera. I find that Images Plus is a bit clunky when it comes to aligning LGBR and narrowband images. It requires selecting different stars for each of the LRGB and narrowband masters. Of course the stars have to appear in all of the masters. I will continue to work on this using Images Plus, but I am also considering trying PixInsight. I have hear a lot of good things about PixInsight - including how easy it is to align masters. The down side is a very steep learning curve. They do offer a free trial period so I may give it a try.

Anyone using PixInsight??

Roger

[Pete]

How's it look if you just do the luminance?

[menardre]

Pete

I re-processed M27 doing a better job of aligning the LRBG, Ha, and Oiii masters. I had to use 5 alignment stars to get all of the frame completely aligned. Not a big deal to do, just have to make sure that all masters contain the same stars. This image is only slightly cropped so you can see the stars surrounding M27.

Roger

M27 LRGB-Ha-Oiii Slight crop.jpg (1.66 MiB) Viewed 1917 times