This project started as a H-Alpha 2x2 mosaic of the Rosette and Cone nebulas in Monoceros. The top-left pane was taken during full Moon (23 degrees away from this field).

You can see the H-Alpha image only here.

After having the Ha, I was hoping to gather LRGB to make a color image, however I could only squeeze one night for RGB before bad weather arrived, and on that night, I only had about 3 hours before the Moon would show up that night, so the only way I thought I could gather some color that I could use was by using my Canon 40D and a camera lens, and that's how I've got the color (18x10'). Not enough time to get separate RGBs and luminance, much less for a 2x2 mosaic.

Since the color data was so bad compared to the Ha, rather than combining the Ha with the RGB and getting a luminance out of that, I used the Ha as luminance - something I wouldn't recommend - then did some needed heavy surgical work to the RGB image and added it over the Ha-made-luminance, which not only created the famous salmon salad effect but also generated undesirable color blotch and other artifacts. Although I do have a version where I tried to transform the "salmon color" into the more accurate reddish color of strong Ha areas, I felt the image suffered more overall, creating even greenish-looking stars! For that reason I decided to make the version you see above - the salmon color image - the "official" image for this project. You can see the "cherry red" image here.

This image was selected as NASA's Astronomy Picture of the Day on February 14th, 2010.

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DATE December 1st, 2009 PHOTO Exposure: Ha: 18 x 20', RGB: 20x10' Focal: 385mm, f/3.6

EQUIPMENT Imaging Scope: FSQ 106 EDX w/Reducer Camera: STL11k Guide Camera: StarShoot Autoguider Imaging Scope: EM-400

SITE & CONDITIONS Home, Sunnyvale, California Seeing: Poor Transparency: Average SOFTWARE Stacking: DeepSkyStaker Processing: PixInsight & Photoshop