DSLR Shots and Discussions

Originally Posted by Titan1080

A tripod is definitely required for shooting the stars. Remote triggers are not necessarily required (but they're cheap and make life so much easier) since you can use your camera's timer to open the shutter without causing the camera to shake, and I don't care how steady your hand is, the image will blur slightly when you push the shutter release on the body itself. My settings vary greatly between shooting in the city and out in the country as well as how long I want the shot. This first one I was capturing a flyby of the International Space Station so I wanted a longer exposure to capture as much of the transit as possible without having the city lights over-expose the sky. This was taken at 10pm last night and the sky still wasn't done transitioning from twilight to night:

18-55 kit lens at 18mm, f3.5, ISO320 for 25 seconds


This second shot is from that campout and I just pointed to a fairly dense area and took a shot. The big difference equipment and setting-wise is that I used my 28mm prime (effectively 42mm for my camera) for this shot and the aperture wide open at f/1.8, ISO800 for 10 seconds. If you're after a constellation portrait, you're going to need a fairly wide angle lens depending on how big the constellation is and what sort of landscape you want to frame it with. The wider your lens, the longer you can leave your shutter open before you start to notice star trails. An f/1.8 setting will give you the shortest exposures but the stars can get a little blobby during longer exposures, especially if you're not perfectly focused which can be difficult to do at night. I usually shrink it down to f/2 to f/2.8, which helps the stars appear more like pinpoints. With just a tripod, you can get good portraits at ISO800 for 10-15 seconds without it being too noisy. Ideally, I'd like to run ISO400 for 20-30 seconds at f/2.8-3.5 but for that I need a tracking mount of the sort you'd find at a good telescope shop to keep the stars from trailing, which is a whole different kind of cool shot but requires you leave your shutter open for an hour or more for some really long trails.

Anyhoo, the advantages of a dark and remote sky are pretty blatant, if I had used the same setup last night, it would probably look like I took the picture in the late afternoon and all but the brightest stars would be washed out. Out in the sticks, the camera can pick out stars that are magnitude 7 or so with those settings, maybe even a little dimmer. The dimmest star a typical human eye can pick out is magnitude 5-ish, and I didn't even see those satellites in this shot. By contrast, the ISS was at magnitude -4 last night, which is about as bright as Venus, pretty darn bright in other words.



At any rate, there are whole books written on just astrophotography so I could go on and on, the nice thing about DSLRs today is that it's so much easier to do the trial and error process and much cheaper than when I was a kid using FujiColor Super G 800 film!