Basic astro-photography from light polluted areas
This whole astro-photography thing is a pain in the cheeks at times. There I was sat in the cold with the telescope last night, tripping over wires in the dark, cursing the GOTO for not being spot on and finally chucking it all in after 30 minutes because the wind was an even bigger pain and it was impossible to get anything worthwhile at all.
I was this close → ← to chucking the whole lot on Gumtree and packing it in totally. Such was the severity of the huff. Thankfully I didn’t but what it’s taught me is not to attempt this stuff when the conditions aren’t perfect.
Less than perfect conditions though don’t stop you having some fun with a nice clear sky, never mind how windy it is and the even better news is that you can do this stuff with some nice basic photographic gear; this post from here on will be a telescope free zone!
All you’ll need is a camera you can control the exposure on (variable zoom will help too), a tripod and a remote control for the camera or at least one with a self-timer. The hardest part is getting the clear sky but even the odd cloud can add to a shot as long as your intended target is still visible.
To demonstrate what’s easily possible, these 4 shots were taken in central Edinburgh, in light pollution with a Nikon D90 fitted with a Nikon 18-200mm VRII lens.
The technique is simple enough, keep the ISO fairly low, around 400 to 640 otherwise the light pollution will run away with your shot. Exposure times will vary maybe from less than 1s in the case of a planet to a few seconds on a star cluster, even as long as 30s on a wide field shot. The whole idea is to get enough light in to give you the shot but avoid stars trailing to get a decent shot.
Finding interesting targets is your next challenge. The sky just now is best after midnight and even with the moon out the way there’s some nice stuff you can get. After midnight the Pleiades open star cluster will be getting higher in the sky and below it will be the brilliance of Jupiter, a nice photo opportunity, especially if you can include some ground interest to give some perspective.
The Pleiades itself is a very nice target and fills the frame nicely at nothing more than 200mm. Keep the exposure shorter when you’re zoomed in like this. The diffractions spikes on this shot were added in Photoshop with a plug-in, it’s not the natural look!
Sticking with 200mm try Jupiter as well! You’ll really need a shorter exposure with the planet so bright take a few at differing exposures and you should also be able to pick up the planets moons.
Winter skies usually provide the best targets but at this time of year you can also get the summer triangle, an easily visible triangle of the very bright stars Vega, Altair and Deneb.
Light pollution needed be a killer but if you do get a chance to get out under really dark skies you might be lucky enough to catch this, the fabulous sight of the Milky Way rising in the sky above…