Rainbows are one of my favorite photographic subjects. They are optical phenomena that cause a spectrum of light to appear in the sky when the Sun shines on to droplets of moisture in the Earth's atmosphere. Rainbows are always opposite to the Sun. The Sun must be at an altitude of approximately 40 degrees or lower for a rainbow to be visible. Many people ignore the fact that using a telephoto lens may produce interesting results like this one. For the whole thing you should use a fisheye lens or create a panorama. The above panorama is composed of 4 vertical shots, stitched together with a stitching software. The shots were taken with an inexpensive point and shoot camera. If the Sun approaches the horizon rainbows are high and they don't display many colors. The Sun at high altitude results to a low rainbow.

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