Atmospheric conditions and sunlight can cause tricks with your vision and interpretation of images that you see.

• A strong Sun with low cloud density can combine to produce bright glaring light conditions during the day.
• Sometimes light allows unlimited visibility and your normal perception of distance can be totally distorted. In this case you will have a tendency to grossly underestimate distance. This is important if you are aiming at a target because you will shoot short.
• Visibility can be degraded by rising heat waves that cause mirages. The heat shimmer distortion is strongest when you look into the sun or through binoculars. Observation is best from a high point at dusk or dawn or on moonlit nights.