Star Trails - In New Mexico 'Round Polaris

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This is another wide-angle (18 mm) shot. One common star trails focus is around the North Celestial Pole (an extension of Earth's axis onto the sky, around which all stars seem to rotate). Everyone is taught that this is Polaris, but in reality, Polaris is fully 3/4° away from the Pole, so in a star trail, it will etch out a tiny circle. I had to reduce the image size to fit on the website (clicking on it will give you a 10" version), but the full 48" version shows this very well; in the smaller one it is noticable.

This image was combined from three exposures, the first at 890 sec, second was 1346 sec, and the third was 623 sec (I stopped because clouds were rolling in). The peach stuff near the bottom are clouds that rolled in near the end. The images were added using Adobe Photoshop, layer mode "Screen." They were taken on September 11, 2005.

Image Date September 11, 2005
Exposure Length 2859 seconds - 890, 1346, and 623 seconds stacked
Number of Images 3 stacked in PhotoShop using Screen layer mode
Camera Canon EOS Digital Rebel XT
Lens Length 18 mm