What follows is the sad tale of why this didn't come out as intended; I was hoping to reproduce a style of star trail shot I saw long ago (and again more recently in this beautiful example of by (JA) ★★) and admired, but I blew it. So be forewarned, if you read what follows you will have no excuse for doing the same! :-)
Still, much better when viewed large on black.
This is a combination of two exposures a 30sec star field shot followed by a 601 sec star trail shot... but I took them in the wrong order and therefore the star field points from the first exposure are on the back end of the star trails, making the sky appear to be turning clockwise...doh! Also, should have left a few minutes between the two exposures so that there would be a small gap between star points and the star trails, doing so would have made the constellations and brighter stars stand out more distinctly from the star trails, as in this beautiful photo by (JA) ★★.
Even though the star field exposure is 20x shorter, the stars look brighter and are bigger because all the photons from each star collect in one (overexposed) area on the sensor versus getting spread out along the star trails which because the trails are not overexposed show the star colors more clearly... which is why its nice to combine the two kinds of exposures... if only I had taken them in the correct order with a short gap in between them... next time! Try it you'll like it :-)
Tip#0: Long exposure first, few minute gap, short star field exposure.
Tip#1: If you can't remember (or like me figure out) what order to take the shots in take a short star field exposure both before and after the longer star trail one!
Tip#2: At night the LCD on the camera even when set to its lowest brightness can still be night vision ruiningly bright. Put one or more layers of ND gel in between the LCD screen protector and the LCD, or tape them over it if your LCD if it doesn't have a screen protector.
Tip#3: When out of the city under a moonless sky instead of a regular white flashlight get and use the Rigel Systems Skylite Switchable 2-Red / 2-White (a very blue white) LED Flashlight The variable brightness thumbwheel means that even if you use the white light by mistake, it starts out so dimly that you can turn it the other/ red direction before you mess up your night vision. This handy flashlight also works well for light painting in red and blue and purple.
UPDATE: My Rigel broke down, and I switched to the Coast dual color LED flashlight. Although it doesn't have the variable brightness feature of the Rigel, the red light works great, has super long battery life, and it's smaller and much more sturdily built. The cons are the red and white buttons are hard to distinguish in the dark (despite that one is smooth and one is rough) and when placed into a pocket or camera bag its fairly easy to turn and leave on by mistake.
30sec & 601sec, f2.8, ISO1600 10.5mm full frame fisheye. N6594&5