Christmas Eve Fun Fact: Bokeh is the term used by photographers to describe the quality of the out of focus parts of a picture. Turns out that the designers of a lens pay nearly as much attention to the blurry performance of a lens as they do to how sharp the in-focus parts are.
By playing around with the aperture value (the size of the hole through which the light arrives at the camera) you can get some quite nice bokeh effects. Try using your camera settings to make this hole as large as possible by using an f-stop value (the unit that cameras use) as small as you can. Great fun with Christmas tree decorations.