Thanks Stephen. I typically shoot sub-exposures from 1 to 30 minutes in length, depending on the brightness of the object being photographed. Exposures of 5 and 10 minutes are probably more common, but for the Horsehead and Flame image, I used 17 exposures of 20 minutes each (340 minutes total) with the hydrogen-alpha filter (red emission line) and added 7 exposures each of 5 minutes duration for LRGB (luminance, red, green, and blue). Total exposure time was 480 minutes (8 hours). Cheers, Tyler
Stephen Peterson said:
Congratulations on the two excellent Trib features! One question; the Trib article on Monday indicated stacked 20 min exposures. Is that correct, as I thought the exposures were shorter (2-5 min)? Steve
_______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://www.slas.us/gallery2/main.php Visit the Wiki: http://www.utahastronomy.com