PHOTOS: How To Photograph The Meteor Shower

We had bad luck catching the northern lights, but tonight and tomorrow could be great opportunities to see the Perseid meteor shower.

Reporter Christopher Dunagan talked with our local amateur astronomer, Dale Ireland, for a story in today’s paper.

I wasn’t sure how to try photographing the Perseids, so I e-mailed Dale. Here’s his answer:

Meteor photography. This is one area where film still beats digital. The linear response of digital sensors means you build up background sky glow very quickly and wash out the meteors. Film reciprocity failure allows you to have longer exposures before the sky and meteor trails are washed out and still capture bright short flashes of meteors. Fast film like asa 800 and a wide open lens, wide angle, 5-10minute exposures depending on sky brightness.
Well, few people including me want to mess with film any more so the digital method is to take a lot of short exposures and add them together in Photoshop. With a lens in the 12 to 28mm range and iso 1600 you can get good shots of about 1 minute long before sky fog is bad and before the stars show too much trail. Then add shots with meteors together in Photoshop. The best method is to mount the cameras on a astronomical equatorial drive and take lots and lots of short high sensitivity exposures. ISO 3000+ with the wide angle lens wide open and exposures in 8-10 second range, one right after the other for as long as you want and can store, plus a couple exposures of a minute or two with lower asa or slightly stopped down to get real nice star field images. Then layer the exposures with meteors together in Photoshop and add that to the nice star field image.
Then you will get a photo like this
http://antwrp.gsfc.nasa.gov/apod/ap091218.html
meteor streaks actually have color, green, red, blue depending on the part of the atmosphere they are burning up in, due to ionized nitrogen and oxygen emission lines.
If you coordinate photography with a friend 10 or more miles away and photograph the same meteor at the same time you can measure the offset against the background stars and use a little trigonometry to determine the height of the meteor. I have done this and it is easier than it sounds.
I forgot to mention that the skyglow around Bremerton causes the sky in images to look very red. You can make this much better by taking RAW images and adjusting the color temperature and tint later. If you don’t take RAW then you can try setting the color temperature to about 3750K or just select the incandescent white balance setting and it will be pretty close. In a really dark rural area a daylight WB setting is good.

Big thanks to Dale for the explanation. If you want to check out his work, head over here to drdale.com. If you’re checking Thursday night, the time-lapse he’s got up is really cool. It’s the fog burning away today, revealing Hood Canal and the Olympics.

– Derek Sheppard