NGC 7293 Helix Nebula in narrowband

[Amaranthus]

The Helix (also known as "the Eye of Sauron") is the closest of the bright planetary nebulae to the solar system (about 700 light years distant), and covers an area of sky similar to that of the full moon (it actually spans about 2.5 light years of space). It represents ejecta from a dying star at the centre, with its outer layers having been blown off over the past ten or so millennia.

This image was taken using a 120mm achromat refractor with narrowband filters (Ha, OIII and SII) and RGB stars. A synthetic luminance was created using an exposure based weighting. The camera was an Orion Starshoot G3 monochrome, upscaled via drizzling. Two different colour palettes (OIII:OIII-Ha:Ha and Ha:Ha-OIII:OIII and HST) are shown.

Captured throughout Oct 2014. Pre-processed with flats (light box), bad pixel map (based on 70 darks) and bias in Nebulosity. Aligned and Drizzled in DSS. Post-processed in StarTools.

Full details and high rez images are on Astrobin: http://www.astrobin.com/135036/B/

[Amaranthus]

Updated the processing and added some false colour tweaks to a 3rd version.

[lazjen]

Nice results. Do you think it would be worth doing longer NB subs?

[Amaranthus]

Thanks Chris. Ideally I'd like longer subs, but the current camera (the G3) mandates drizzling, and this in turn needs a LOT of subs to work effectively in increasing the pixel resolution. So it's a bit of a trade off. With a higer-rez camera, I would definitely be aiming for 30 min subs. Here I went for 10 min, but I think in the future with the camera I'll use 15-20 min subs as a compromise :)

Oh, and I do plan on getting a more advanced camera in the not-too-distant future!

[Rex]

Nice details Barry. Great stuff!

[Ross G]

Nice photos Barry.

Good detail.

Ross.

[Amaranthus]

Thanks Ross and Rex, much appreciated. They're not perfect by any means, but I think pretty decent for an achromat that was never meant for photography...