It is the holiday season again. You may be tempted to take photos of the beautiful Christmas lights. How about getting creative and shoot them out of focus? The result is the beautiful and dreamy light circles like what you see below the title of this post.
To get the best result, setup your camera on a tripod, set the aperture to the largest possible on your lens, and set the focus to manual mode. While watching through the viewfinder, adjust the focus distance of the lens to until you get the effects you like. Due to the presence of the viewfinder optics, the scene you see in the viewfinder may be quite different from what you capture.
As shown in the illustration below, the size of the light circles becomes larger as you focus the lens closer to the camera. At certain point, the circles becomes too big and overlap into an unattractive pile. You may want to take a few test shots to decide the best focus distance.
The out-of-focus light specks always match the shape of the lens aperture. If you stop-down the lens, the circles will become polygons. It also becomes difficult to create the blur effect with stopped down lens. For this type of shots, lenses with 50mm or longer focal length and large aperture (f/2.8 or larger) work best.
To get more creative, you can change the shape of the out-of-focus light specks. You probably cannot modify the aperture in the lens, but you can cut out a shape you like in a thick black paper and attach it to the front of your lens. It is better to center the cut-out to the center of the lens and make sure it does not move. Off-center placement of the cut-out will cause redistribution of brightness across the frame. If you have a Cokin filter holder, simply make the cuts on a card with appropriate dimensions. For example, with a star-shaped cut-out, you can get something like the following.
To make it more interesting and practical, you can try to get a subject between the lights and camera. By focusing on the main subject, you can turn the out-of-focus lights into a nice background. Or you can get the lights between a remote subject and camera. This is a photo in which I focused on the Moon but included some of the Christmas lights attached to the roof shingles.
Keywords: Bokeh, Christmas Lights, Focus, Lens Blur, Out of Focus, Photo Tips