Christmas lights can be a lot of fun as a photographer...
One of my favorite things to do is to make them fuzzy little highlights in the foreground or background of a photo. All of these photos involve Christmas lights hung on the side balconies of Terrell ISD's Performing Arts Center.
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Opening up to maximum aperture (in this case, f2.8), will do the trick, especially if the lights are a good distance from the subject. Using longer telephotos make the background look closer, and the out-of-focus effect will be great, like this one from backstage, behind the elves. (just wish I could get some smiling parents in there too... could not find the angle.)
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Canon 40D, 120mm at f2.8, 1/125, iso800
For a really cool effect, put the lights between yourself and your subject. Up on the balconies, you might think that the lights are in the way...
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Canon 40D, 115mm at f2.8, 1/200, iso80
... But if you focus through the lights to your subject, the lights turn in to little dots of translucent light over your subject.
Canon 40D, 115mm at f2.8, 1/200, iso800
With some careful composition, you can find a point of interest and frame it with the lights. We cropped this one down a bit for the newspaper, but the group of musicians in the center becomes the focal point when the rest are obstructed by dots.
Canon 40D, 200mm at f2.8, 1/160, iso800
You can also use lights on a tree to frame one side of a photo with lights... this one with colorful lights was on the far edge of the stage.
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Canon 40D, 200mm at f2.8, 1/125, iso800
To make it a really cool photo, you also have to catch a great moment, which didn't happen with the shots above.... my favorite shot from the TISD Christmas programs was during a choir concert... alas, no lights. Poor girl almost got slapped in the face.
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Canon 5D, 200mm at f2.8, 1/200, iso 1000
Have fun playing with the lights....
don j.