Help with shooting the stars :)

Hello Everyone,

Last night i tried shooting the stars in the night sky and it didn't go so well. Can anyone tell me how to shoot the stars. I like to take one like how you would see them if you were looking up at the sky. What would i set my settings to. I have a xsi with both a 50mm lens and also 55-250. Thanks!

Hi Michille. With your current gear I would recommend choosing a location that has a dark northern sky and have a try at some star trail shots around the celestial north pole. Your 50mm will work great and low ISO settings(200ish) will work well since you'll be exposing in "bulb" mode for exposures around 30-45 minutes. Focus can be achieved manually on the brightest star you can find, just be sure to adjust your camera viewfinder dioptric dial before starting. Adjust it until the stars get as small and pinpoint as you can get them, just get rough focused with the lens first. You'll know when you've reached sharp focus by the spikes projecting around the star. Another way is to switch to autofocus on camera and lens. Then place the focus sensor box on the bright star until the camera snaps to focus. Then switch the lens and the camera back to Manual and point the camera at the part of the sky you want to image. Be careful not to touch the lens and knock it out of focus in the process. You'll need to be in Manual(bulb) to get the very long exposures needed for star trail. Of course you'll want to use a sturdy tripod, mirror lock and a remote shutter switch as well. Also, try to find some interesting foreground objects of interest(i.e. trees, windmills, barns, etc,) to include in these type shots.

For shooting away from the celestial north pole, for non-trailing stars you'll be limited to around 10 seconds or so at 50mm before trailing becomes obvious. For these you'll want to use ISO 800(possibly 1600) because of the exposure time limitations. And of course dark skies can make all the difference in your results.

Hope this helps.

That helps out a lot. Thanks a bunch I will defiantly try this on the next clear day .

Nighthound wrote in post #7031939
...you'll be exposing in "bulb" mode for exposures around 30-45 minutes.

You mean 30-45 seconds don't you?

What f/ratio is your 50mm Michelle? Is it the f/1.8 or f/1.4? Great light-gathering potential, and you'll be able to get loads of stars captured with exposures as short as 5 or 6 seconds. As Steve says, much longer and trailing will start to appear.

If you're able to get a wider-angle lens, (around 18mm), then these tend to make better star-field images, plus you can expose for that much longer before trailing becomes a problem. Something like 20s at 18mm. 30s at 10mm is pretty okay too.

Adrena1in wrote in post #7057757
You mean 30-45 seconds don't you?

I was referring to star trails around the celestial north pole for the "spin" effect. Of course exposures of this length require very dark skies. I'm limited to around 20-30 minutes even at my darkest location. Honestly though I haven't tried it in years, probably more LP now then back then.

Let me stack a couple of (hopefully) relevant questions on her thread.

You know I've been exclusively lunar so far but I'm looking to branch out, so I got an EQ1 mount, a motor drive, and an overpriced switch to hold the shutter open on bulb. Thought I'd try some long exposures though a wide lens, maybe 17 mm on my 50D, with and without the drive running.

1. How long can I expect to hold the shutter open and the mirror up on bulb before the batteries run out?

2. Can I mechanically lock the mirror up to extend battery life?

3. If I run the clock drive, at ISO 800, how long do I need to expose? I know the alignment will affect this, but how long until I get about all the stars I'm gonna get in a wide-field shot, say down to mag 13 or so? Minutes or seconds?

I did some test shots at 30 secs at ISO 800 and got mag 10 easy, and hints of 11.

Thanks for your help in advance, like michellebaker I'm looking forward to a new angle on my hobby.

I've never exposed much past 30 minutes but certainly you won't have to be too concerned about battery life unless you shoot in severe cold. Temps at or below freezing cut charge life down considerably. In my experience the camera has always finished the exposure before shutting down or giving the replace battery symbol on the camera read out. I really only know it's time for a battery switch when I try to look at the shot on the LCD and it doesn't display, I then look on the display and see the dead battery symbol, shut the camera off and replace battery with a fully charged unit. I shoot multiple 4-5 minute exposures and get around 20-30 shots on a full charge when it's not freezing cold out. On very cold nights it's about half that.

Reviewing images on the LCD is huge in power consumption but necessary for me until I'm sure everything is set to go.

With a release unit you'll have to use mirror lock and click twice to lift the mirror and begin the exposure each time. When you stop the exposure the mirror will come down. I don't know of a way to keep the mirror up or if it would be significant in saving power.

I would test your drive to determine your exposure limits. Alignment accuracy will be very important as well as balance. I would think at 17mm you could get upward of 2 to 2.5 minutes but I really can't say not knowing the mount. How fast is your 17mm?

And of course, the darker the skies, the better the results. Good luck and post some tests, I'm curious to see how things are operating. Clear skies.