Four-hour exposure, ISO 200, 14mm at f4, NO dark-frame, no noise reduction in post, 100% crop. The stock Nikon battery had 16% left, 35 degrees F. The file is very clean and I'm really surprised that the darn battery would last this long. I'll be doing an eight-hour exposure next dark moon cycle using an external battery to see what that looks like. Could this camera be as good as film for star-trail photos?