| Description: | Unfortunately this beautiful planetary nebula is always located very low in the sky over here. To get a good view you have to travel south, and so I did during the holidays. Daytime temperatures in Southern France were around 35°C and between 25 and 20°C at night. Fortunately my new CCD camera has peltier cooling that can lower the dark current noise by a factor 2 for each additional 7°C of cooling. The minimum temperature I could reach was -10°C, so that equals at least a sixteen fold reduction in noise.
With my previous camera, an uncooled Canon 40D DSLR-camera, I could never have achieved a result like this under the same circumstances. Image details: 7 x 10 minutes of luminance through a clear filter and 3 x 10 minutes each through Red, Green and Blue filters. Camera: QSI583 CCD camera with 8.3 Megapixels (5.4 micron square). Telescope: 20cm f/2.8 ASA Astrograph. This is image is a crop of the full size image that was assembled from the four separate monochrome images using Photoshop. |
