RBA Premium Astrophotography

November 16th, 2009

Witch Head Nebula and Rigel

Posted: November 16th, 2009



Here's my "November 2009 project"!

In this image I first tried to put into practice a method to pull the dust out that I had been thinking these past few days, and I didn't end up too thrilled about the results. It induced some "blur/denoise-like" effects early in the processing, and it also fabricated bloated star halos in the mid-sized stars (Rigel was put where it belongs with a quick HDRWT).

So after the fact I went back and did some reprocessing from scratch treating large and small scale structures separately, then merged the results to the previous image. This helped me reduce some of the halos (I did't bother with the big ones because those are "optical presents" not the effect of bad processing), keep the stars under control, enhance the witch head a bit, etc. but didn't remove the denoise/blur effect on the background.

I still think the initial processing thingy may work, I just need to play with it a bit more and be more careful next time... Nevermind the halo aroud Rigel is purple, although that's how it came out.

The image is in fact a 2 pane mosaic with data from 3 frames, each taken from a different site, with a total exposure of almost 12 hours.

This image was selected as NASA's Astronomy Picture of the Day on December 29th, 2009. and then also on November 1st, 2012.