Hi All,
I’m pleased to present my last image for the year ‘07. I was attempting to stay away from the “mainstream” objects, but couldn’t resist targeting this one while I waited for a few other summer targets on the list to rise. So here it is –
IC434, The Horsehead Nebula.
One of the many celestial showpieces located in the constellation Orion is the Horsehead (IC434) and Flame (NGC2024) Nebulae. The Horsehead nebula (also known as Barnard 33) is seen center of frame. It’s a tower of dark dust and gas which harbours the embryonic stages of young stars. The nebula is surrounded by energised hydrogen which glows vibrantly red. The Horsehead nebula resides 1600 light years away.
To the lower left of the Horsehead is the beautiful emission nebula known as the Flame. The very bright star Alnitak (Zeta Orionis) excites the Flame nebula which glows a variety of colours, from yellow to orange, though the predominant hue is pink. It is approximately 900 light years distant.
About the image;
The image is a Ha+[HaR]GB composite consisting of a total exposure time of 5.7 hours (Ha: 165min, R: 60min, G: 60min, B: 60min). It was acquired over two nights while the object was high. The resolution shows as the details obtained in the Ha data are quite profound especially for a 530mm focal length instrument. I’m somewhat disappointed by the filter reflections on the bright stars. There is little that can be done to minimise these. They were much worse, but with masking I’ve restored something which I feel is more “palatable”.
Data exhibits some noise, need to redo calibration frames over the break. This was an interesting object to process, which lead to experimenting with a few different techniques. In particular RJ Gabany’s softlight colour process which gives lovely rich tones. It worked well (perhaps too well) and counteracted the typical salmon pink found in HaRGB images and amplified star colours. I also took some luminance frames, but decided not to integrate them – only Ha was used as the luminance. I know I can do much better with this target, but this is will suffice for now considering it wasn't on my planned targets list. Anyway, if you want to know specific processing details, simply PM me offline.
Hope you enjoy it.
I’d like to take this opportunity to thank all IIS members for their continued support and enlightenment. I obtain gratification contributing to this great community. I wish you and your family a Merry Christmas and a prosperous New Year. Take care on the roads. I sense 2008 will bring some magnificent images from us all.
All the best.