A polarizer is a circular polarizing filter that you screw onto the front of your camera lens. You can spin it around, and it has a variable effect depending upon its position. The effect on your photos is based on a number of other factors, including where the sun is and the angle you're making with respect to the reflections or the sky. To get the right effect, you need to consider all of these factors when you frame your photo.

See "" for tips on getting the most out of a polarizing filter.

I recently saw an ad for Apple that says it can help organize photos for you based on face recognition. How long will it be before something like that is available for Windows users so that I can better organize my photos?--Kathleen Diehlmann, Highland Springs, Virginia

Apple might be actively advertising face recognition (and to be honest, I haven't seen those ads myself), but rest assured that there are several programs for Windows with face recognition technology built in.