Tuesday, 6 March 2012

No spaceship needed: Taking close-ups of the stars

LOS ANGELES – Most evenings, Brian Valente can be found outside his home here, staring up at the sky.

He's got his digital SLR connected to a slick 12-inch telescope to take long exposures of planets, stars and constellations. He's got his iPad 2 by his side, with the SkySafari app open, showing off augmented reality images of the solar system.
"I'm curious about the natural world," he says. "It's amazing to see how much stuff is actually out there. And you don't need a spaceship to see it."
Valente, 45, who works in the video business as co-founder of Redrock Micro, a company that makes cinema accessories, has been taking pictures of the stars for three years.
What began as a lark — capturing a picture of a nice sky — turned into an obsession that finds him spending many evenings behind his camera and telescope.
He's not alone.
Jerry Lodriguss quit his job as a photographer for The Philadelphia Inquirer in 2009 when sales of his books on astrophotography surpassed his journalism salary. He won't say how many books he's sold but says the books are how "I make my living."
Lodriguss runs the Astropix.com website, a resource for astrophotographers with oodles of images he's taken of the moon, Saturn, the Milky Way, stars and constellations.
"When you look into outer space, you're looking back in time," he says. "It's taken millions of years for some of these stars to travel. I never cease being amazed by it."
Digital technology, he says, has done wonders for making astrophotography easy and affordable, with few extra tools needed.
Because most of the readers of his Astropix.com website are photographers who are new to astrophotography, Lodriguss makes a point of shooting stars with cheap, consumer cameras.
His camera of choice is a Canon Rebel T2i, a digital SLR that can be found online for about $650. He also uses the cheap "kit" lens that comes with the camera, instead of the more expensive, fancy lenses that Canon targets to pros.
He's tried shooting the stars with point-and-shoot cameras, but he says they don't do the job well. Instead, he recommends using a digital SLR — even an entry-level model such as the Rebel.
Lodriguss' tips for starting out with astrophotography.
•Put the camera on a tripod to steady the image.
•Use a DSLR and try your hand at a wide-angle view of the sky. Lodriguss recommends setting the lens at its widest opening, around 3.5, and an ISO rating of 1,600.
•Don't shoot in auto mode. In manual mode, you'll be taking long exposures of the sky, around 20 or 30 seconds each. Most photos down here on the ground are usually taken ultrafast — at 1/60th of a second or 1/125th of a second.
•You'll need a shutter release for the long exposure, which plugs into the side of the camera. Decent releases start at about $15. For exposure, you'll need to put the camera dial on the B, or bulb, setting.
•Digital cameras have settings for color balance and are generally tuned to daylight. Lodriguss says to switch to the tungsten setting, which is for artificial lighting but works best with the sky and stars.
Wide shots will look best initially, Valente says, because when you start looking at the sky with a big telephoto lens at a slow exposure, you'll encounter visible streaks — from magnifying Earth's rotation.
Graduating to a telescope — which start around $1,000 at Telescope.com — and an accessory equatorial mount for $500 will solve that issue, Valente says. The mount moves the telescope with Earth's rotation and gets rid of the streaks.
Valente took his first astrophotograph in 2009 and within six months had started hanging around his local camera shop, which also sold astronomy equipment. To get even closer, he graduated from a long telephoto lens to a telescope that connects to his digital camera.
Lodriguss uses a 5-inch telescope as well, to connect directly to his camera. It's the equivalent of using a 1000mm lens — most sports photographers use 300mm and 400mm lenses to get closer to the action. With a telescope, he's nabbed images of not only the moon, but also close-ups of craters there.
Winter photos of the galaxies produce more nebulae (those big gaseous clouds), while summer produces more galaxies, Valente says.
Unlike visits to remote rural areas, where the sky looks much brighter, putting a nice lens on your digital camera and pointing it to outer space won't suddenly make stars and planets look closer and brighter, Valente says. You'll see that after you take the long exposure and view it on the camera's LCD screen.
Los Angeles smog makes seeing into the sky tough for the naked eye, he says. "So when you can look at the back of your camera and see something you couldn't see with your eye, there's just something totally captivating about it. It's like when you developed your first picture."