This is one of the most colourful examples of a Sun Dog I have ever seen. A sun dog is a beautiful example of atmospheric optics. This is a term used to describe the interaction between light and our atmosphere. You may have heard a sun dog described as different things. It's different names include a parhelion or mock sun. The cirrus clouds present in this image are a type of high level cloud. On this particular day they are all contrails.

The beautiful spectral colours of a sun dog can be found at 22 degrees, either side of the Sun. This photo was taken on a really cold day, -13 degrees centigrade! Hexagonal plate shaped ice crystals high in the atmosphere refract light. If millions of them refract light in just the right way we get a sun dog or sun dogs! A sun dog can also be part of a larger 22 degree halo. These phenomena are known as Ice Halos.

There are a great range of atmospheric optics that we can observe and photograph. Take a look at the atmospheric optics page of this site to see more examples. I took this photograph of a sun dog at Patmore Heath in Hertfordshire. Patmore Heath is an SSSI. That is a special site of scientific interest. This is due to the diverse range of wildlife and plant species found living there.

Exposure Information

Camera: Canon EOS 450D

Lens: 18-55mm lens set at 55mm. I zoomed in as I wanted to show you the spectral colour of the Sun dog. However I still wanted it in the context of the surrounding landscape. A foreground is very important in weather photography.

Shutter Speed: 1/1000th of a second. It was a bright day so I used a very fast shutter speed. This also helped in picking out the colours you can see. The slight compromise was that the ground is somewhat darker than it should have been.

Aperture. I used an aperture of f/9. This small aperture meant that a good depth of field was present across the whole frame.

ISO 200. I used a low ISO of 200. This helped minimise noise and grain. A low ISO meant that I did not over expose this photo of a sun dog.