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Дата изменения: Unknown Дата индексирования: Sat Apr 9 22:53:49 2016 Кодировка: Поисковые слова: дендрохронология |
Analemma
Kiev-60, Flectogon 50/3.5, N-4 filter, Kodak Ektar 25.
Multiexposition 34 images Sun 1/1000 sec f/22 and 1 image background.
| I should say it is the most complicated photograph I have ever made. It shows position of the Sun on the sky in the same time of a day during one year. Analemma - a trace of the annual movement of the Sun on the sky - is well known among experts of sun-dials and old Earth's globes as a diagram of change of seasons and an equation of time. Between August 30th 1998 and August 19th 1999 I have photographed the Sun 36 times on a single frame of 60-mm film. The pictures were taken exactly at 5:45 UT (Universal time) of every tenth day. Previously, the position of the Sun on the sky was calculated with computer as well as optimal moments of time for taking each of the exposures. However, my success was strongly limited by the weather. Nobody can guarantee fine weather every tenth day even for a few minutes. Approximately, there are 120-170 sunny days a year in Crimea. That made me sure that my aim could be achieved. To do the job, the camera must stay fixed during 12 months. It was difficult to find such a place where the camera would be safe. The solution of the problem was to make a plug-in platform rigidly connected to the camera, which allowed to keep accurate position of the camera during next mountings. Thus the platform with the camera could be mounted and dismounted repeatedly. I use "Kiev-60" camera with the lens "Flektogon" 4/50 and neutral filter N-4. Vertical field of view of the objective is about 50 degrees which allowed to photograph all the "figure-of-eight". The exposures were 1/1000 seconds with the diaphragm 22. When the weather was bad the shooting might be postponed for 1-2 days, but not longer. Due to bad weather conditions I had to miss 2 exposures (November 26th and June 20th); the operating schedule was shifted but it had almost no influence on the appearance of the resulting picture. The background photograph was taken on 10th July 1999 in the evening. | |
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