This is a simple trick from pro photographer Jesse David McGrady to create hazy photos, with the center almost clear and the edges foggy – for atmosphere. First, take a small, clear plastic bag, and rip a hole in the bottom. Don’t use scissors; you want a random edge.
Second, slip the bag around the lens (yes, this works only on a camera with a standard lens, not a pocket camera). Make sure the ripped end of the bag sticks out a little beyond the end of the lens, but make sure the center of the lens has a clear shot (if you want clarity near the center of your photo). Third, snap away like a pro. BONUS TIP: Use a marker to add random color to the plastic bag and see how that changes the mood in your photos.