Be on the lookout for intruders trying to make their way in to your pictures. Branches, out of focus grass blades, telephone wires – all these and more can act as distractions.
Most camera viewfinders show only about 92-95% of the image. Keep that in mind while photographing. You may want to try shifting your camera around to see what’s at the edges.
Some intruders are hard to see in the viewfinder simply because they’re too close and not in focus. When you get your pictures back you see things you didn’t see before. Remember, you’re looking through your lens at its widest aperture. Accordingly, you’re looking at things with the shallowest depth of field. Some things won’t appear to be in focus. Use your depth-of-field preview button, and you’ll see any intruders. If you don’t have a preview button, try focusing throughout the range of your lens to see what may show up.