If you've ever noticed how beautiful lights can look when they are out of focus, you'll probably already have realised that we're about to enter the high season of everything that's awesome in the field of bokeh-liciousness. That's right - Christmas lights are pretty much the holy grail for gorgeous out of focus light effects. But how do you create the effect?
Step 1 - Pick the right lens
One of the most important things you're going to need to capture good bokeh, is that you need some great out-of-focus areas to begin with. So: Grab your lens that has the widest aperture (so, the smallest f-stop number). If you've got a prime lens, that's probably your best bet, but it's also possible to use a long zoom lens.
If you're shooting with a zoom lens, you'll want to zoom in, and focus on something close to you to get the maximum depth of field effect you're looking for in this particular case.
Step 2 - Pick the right aperture
The next step is aperture. If I'm shooting exclusively for depth of field, I'll be shooting in Aperture Priority. Start in the biggest aperture you have (the smallest number, remember? If that doesn't make sense, quickly brush up on your skills with our Why is the F-stop scale so weird article).
Don't blindly go for the largest aperture though - it's a good starting point, but I often find that on some of my lenses, that means the foreground is a bit much - experiment to find the best settings!
Step 3 - Find a foreground
A big blurry mess can be abstract and interesting, but let's be honest: It isn't storytelling, which - as we know - is one of the most important things about photography. So: In addition to the beautiful blurry mess, you also need to think about what the story is that you're trying to convey. If it's Christmas, it shouldn't be hard - get baubles, presents, kids, or food into the photo as well, and you're probably half-way there.
Step 4 - Keep experimenting!
The world of bokeh is lots of fun - so keep that lens stopped wide open and start pointing it at light sources. Busy cities, gorgeous christmas trees, and even the TV can be a great source of beauty. Have fun, explore, and do share some of your best results in the comments!
Finally, don't forget that bokeh isn't just for the background - if you're feeling brave and adventurous, switch things around and get your background in focus instead - like in this great example from Mikko.