We are all fascinated by the universe and the possibility of life elsewhere, whether that's us or something alien to us. It's one thing to know there is a moon, planets, and stars around us, and then to realize that they move... that's crazy! You look up at the sky at night... it looks the same as the last time right? No... it's always changing, because we're moving and objects out there in space are moving too! I hope you read that like Bill Nye, the science guy... if not, please do. It's just hard to see the movement looking briefly with the naked eye, until a star shoots across the sky, or there is a meteor shower. Well the brightest meteor shower of the year just happened, and while us star-gazers are happy with just taking it all in with the naked eye and wondering what's going on up there, others are trying to capture the moment to get a closer look...and still others, studying their findings to further scientific discoveries and exploration. You Astronauts are hopefully looking at this like a professional surfer looks at a wave off the Hawaii coast...an absolutely amazing occurrence, although you've seen vastly greater.
Words really can't explain the feeling that comes from being wrapped up in a sleeping bag, temple to temple with your special someone, peering into the night sky, not knowing what's out there or even in the woods around you. (It's funny how the dark unknown of the sky can be comforting when you're in the dark woods, and how knowing what might be in the dark woods can be comforting when imagining the unknown dark sky.) And to know that you've got your camera set up on a tripod, in just the right location at the perfect angle, so that you can accurately capture that moment in time.
Between the hours of 1:00 AM and 4:00 AM, over the dark waters of Jordan Lake, on a clear night in August, one day before the new moon - the Perseid meteor shower was in full display!
So how does one photograph a meteor - particles flying through the Earth's atmosphere ranging in size from about that of a small pebble down to a grain of sand, generally weighing less than 1-2 grams, traveling at speeds ranging from 25,000 mph to 160,000 mph, and visible for less than half a second ???
1. Use a wide angle (Pentax 12-24 f4 ED AL) lens focused to infinity, with a 15 second exposure on an interval timer, take one shot of the night sky every 30 seconds for 3 hours.
2. With the aperture wide open (f 4.0) to capture as much light as possible, underexpose the shot by -1 EV to balance the foreground.
3. Use a high ISO, like the photographs above set to 800, to balance light sensitivity vs noise.
Oh, and possibly most important, apply foot warmers (yes the camping kind, with hairbands, thanks to my sweet wife - a rubber band works too), to the outside barrel of the lens in order to reduce condensation on the lens as the temperature drops throughout the night.
Another successful method is to use a higher ISO (1600-6400) and longer exposure time (30-60 seconds) to catch more "background" stars in a single frame. However, when doing so, there is a rule of thumb - "the rule of 600" - to remember when doing astrophotography. Take 600/(lens focal length). This gives you the slowest shutter speed you can use before noticing motion blur in the stars (because you are constantly moving with the Earth's rotation). For a 12mm lens as the one used, the shutter speed should be kept below 50 seconds so that the stars do not appear blurry.
And if you find yourself wanting to try this method, don't be discouraged if things do not turn out just how you planned the first go around. It takes a lot of patience, and most of those brilliant astrophotography shots out there use stacked compositions (stacking several photos of a time-lapse on top of one another in special software) or a GPS motion tracker on the tripod ($$$).
So the next time you hear of a special celestial event, or are just looking up at the stars, wrap your brain around this final thought...
Though theory states that the universe is constantly expanding into eternity, that is not the whole story. As some new celestial bodies are created, the universe is actually dying. Stars are continually imploding and the energy of the universe is dwindling. Ok you science nerds - it is being conserved - but the number of stars in the sky is always in flux. So... next time you look to the heavens at night, do not take it for granted. Though it may take thousands of lifetimes, those familiar constellations, that bright north star, those guiding lights... will not always be there.
Stay tuned for additional photos from that evening and check www.GreinerStudio.com for more...
Astronomy facts within this article provided by:
http://www.amsmeteors.org/
http://www.npr.org
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