Opposition Effect from Different Viewpoints

When the surface is too far away for your shadow to be visible there is just a brightening around the anti-solar point. Without a shadow for reference this effect is easily missed.

Opposition effect from a hill Opposition effect from a hill

This was taken while I was standing at the top of the hill. The brightening around the anti-solar point appears to be slightly elongated in a vertical direction, probably due to the the way vertical stalks in the wheat field hide their shadows.

Part of the way down the next hill and the anti-solar point is on the hill opposite. This time it falls on short grass and is not as distinct.

Opposition effect and individual shadows Opposition effect from a ballon

The opposition effect makes it quite easy to work out which person took this photograph. Of course each of the other two people thought the glow was around their own heads!

Here the faint glow also extends well below the main shadow almost to the bottom of the image. This is probably because of the way the vertical leaves of the crop cast their shadows. It was more obvious at the time than the image suggests because of the movement of the balloon.

Other Glows Topics