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My Astronomik CLS-CCD filter arrived and I want to give it a trial. Wanted to see how long exposure I could make and still have some data in the sub that is not overwhelmed by the light pollution. So I set the camera in my balcony, no tracker and start to try longer and longer subs: 5 min, 10 min, 20 min and 30 min.

I was surprised that the 30 minutes exposure still have so much information. Because of the filter, there is a blue cast through out all the picture, which I knew it would have, so i wanted to edit the picture to practice removing it. The result is my first Star Trail:

Star TrailsPolaris in the middle (unstacked)
Focal Length: 70 mm
Aperture: f/4
ISO: 800
Shutter: 1860s
Tracker: None
Stacking: No
Total exposure: 1860s
Filter: Astonomik CLS-CCD
Taken Aug 16th, 2013 around 00:42 CEST

Not the best star trail out there, but quite good for my first trial. Will try better ones in the future, with some landscape around it.

It was a hard job to remove the blue and calibrate the colors in Pixinsight. My first trial was a disaster, them tried again twice. Just the 3rd time that I believe I got it. The process is a bit indirect, since I have a raw RGB image that I need to convert to a Grayscale CFA and then de-Bayer to get back the RGB colors. Just them do the Background Neutralization and the Dynamic Background Extraction. But the final result was quite nice. =]