Keen eye of the man with the golden sun
The view from Buffalo ... an amazing view of the sun, photographed from a backyard in New York. Photo: Copyright Alan Friedman, avertedimagination.com
FROM his backyard in downtown Buffalo, New York, self-titled space cowboy Alan Friedman is capturing images of the sun - 150 million kilometres away - that have spread around the world like wildfire.
Mr Friedman started taking photos of the sun, the moon and the stars in the mid 1990s but his passion for solar imaging began in 2003. That's when he purchased ''a magic glass'', as he calls the hydrogen alpha filter that let him capture the loop-shaped eruptions of luminous hydrogen gas (called prominences) from the sun.
The switch to solar photography was also pragmatic. ''Buffalo is cold and cloudy, and not known as a mecca for astronomy,'' he said. ''The view from my backyard is not exactly an ideal spot. It's got telephone wires, power lines, cable TV lines and rooftops.''
Like wildfire ... Friedman's images of the sun have been circulated around the world. Photo: Copyright Alan Friedman, avertedimagination.com
An industrial city on the edge of the Great Lakes, Buffalo gets only 60 clear days a year, he told Fairfax Media in a phone interview. And the bright city lights make it impossible to see the faint objects such as galaxies and nebulae.
Mr Friedman often tints his images. His most famous photo was of the sun, tinted orange for Halloween, which he titled It's Not the Great Pumpkin, Charlie Brown. The image went viral, appearing in newspapers and websites around the world.
Mr Friedman said part of the appeal of his amateur images was that they inspired others. ''Images by an amateur or a citizen astronomer are compelling because they get you off a couch to do something, whereas Hubble Space Telescope images, because they are so spectacular, they push you into a couch in awe,'' he said in a Ted talk in his home town.
He said there was no place like home to get started. ''There is also no place like the backyard … and that's where discovery begins, because you can be there any day of the week any time,'' he said in the Ted talk.
Mr Friedman's solar photography takes place in the morning and in the afternoon from his backyard. He said he was getting older and and was losing the drive to sit out in the cold into the wee hours of the morning.
''To record my images, I use a filter that passes only a narrow slice of the deep red end of the visible spectrum. Called a hydrogen alpha filter, it is attached to the front end of a small (eight centimetre aperture) telescope. Think of it as a 450 millimetre f5 telephoto lens,'' he said.
He recorded his images using an industrial webcam, the same sort police use to capture speeding motorists at a red light camera. Because it was so hard to get shots of the sun without movement, he described his attempts as being akin to guerilla warfare.
''I look for moments of steadiness. The video allows me to capture tens of thousands of frames but there are only microseconds when they stabilise,'' he told Fairfax from Buffalo.
''By the end of a session, I usually have a few minutes and 50 gigabytes, easily, of data.''