What is an analemma? A typical definition would be: "a scale shaped like the figure 8, showing the declination of the sun and the equation of time for each day of the year." That may not help much, so think of it this way: If every few days, at exactly the same standard time of day, an observation were made of the sun's position, it would be noticed that the sun's location changes slightly both up and down, and also from side to side. Over the course of one year, the changes in the sun's position describes an elongated figure 8 stretching across about 46 degrees of the sky. It is this pattern which makes the analemma, and this is what I captured on film with Keppel Henge in the foreground. The photo is shown on The Analemma Project page 1.
At present, only a few analemma photographs are known to exist. The reason that so few photographs of analemmas have been made is because there are some daunting technical challenges that start with positioning the camera properly to take in all of the figure during the course of the year. The figure 8 image is created by collecting multiple exposures throughout the year. I photographed the sun every ten days, on average, making 35 multiple exposures on one frame of film, that lined up to form the finished image. An additional image was made of the landscape without the sun in the frame to give context to the photo, for a total of 36 exposures. As an added challenge, the camera was located out in a field, most of the existing analemma photos were taken through a window.
The two photos below show the basic set up of the camera. A number 12 welder's shade was held over the lens for the sun exposures. The camera is a Canon A-1 and is designed for taking multiple exposures. It is fitted with a 28 mm lens set to f2.8. The shutter speed was 1/250 sec. I used Kodak Gold Select 100 print film. The camera was positioned and locked in place on a wooden mount and that in turn was bolted in place for the exposures and then removed for storage between exposures. Our seasonal weather here in Canada is much too extreme to leave the camera in place throughout the year. A special wooden box was made to carry the camera and mount out to the henge site for the exposures, and for storage. The photo on the right shows the 4 by 4 wooden post that the camera mount was bolted on to. The post is set in concrete.
It was an interesting process working on this project during the year. It required equal doses of planning, luck, persistence and optimism. There were some real challenges with the weather. Keppel Henge is located at 44° 47.403'N Lat. and 80° 56.682'W Long., at an altitude of 187 meters above sea level. The winter months were the most difficult stretch. Winters at the Keppel Henge site can be very snowy and quite cold. We had a total snow accumulation during the winter of 16 feet, and that made it a little difficult to get out to the henge site. I just had to give myself a bit more time to get set-up for each exposure. This winter was cloudy as well. Keppel Henge is surrounded by the Great Lakes lakes so huge that they generate their own weather systems and lake effect clouds are common during the winter months. We can go weeks on end with hardly a sunny day, and that was the case from mid-January until the end of February. However, the winter also held some of the best moments too. Like finding fresh coyote or deer tracks in the snow by the henge. One very bright but cold winter morning I noticed a pair of delicate, rainbow hued sundogs on either side of the sun rising gracefully with it above the horizon. I also remember how happy I was to see the sun image well within the camera frame as it rounded the ends of the figure. It meant that the planning done many months earlier had been correct and that I wouldn't have to start over again!
Why not try your own analemma photo? Each one is totally unique, and so is the experience of attempting one!
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