A total
Sun eclipse occured on 29th March 2006. The weather was very good in all southern Turkey. The sequence photo was taken by
Jukka Ruoskanen on a beach close to the town called Side in Turkey. Few minutes before totality high clouds came, and a halo was seen. The halo, of course, vanished with the sunlight and reappeared again after the total phase - the high clouds responsible for the halo can be seen in some of the photos. The sky colours were truly amazing with deep bluish hue towards the zenith and a great "sunset-like" appearence all over the horizon. The other noteworthy points were a significant temperature drop and the peculiar light some minutes before second contact. At that time the shadows were really sharp too.
The second (16 mm) wide-angle picture of the sky during the totality of the 2006 eclipse is taken by Günther Können in Colakli near Side at the south coast of Turkey, straight on the central line. The horizontal field of view is 135 degrees. At the 4 o'clock position fron the overexposed corona, Venus is visible. The limiting magnitude during totality is +3, about the same as during twiligt with the sun 7 degrees below horizon. The light of the sky occurs because of leaking of light via the horizon, from regions where the sun is not completely eclipsed.
A total Sun eclipse occured on 29th March 2006. The weather was very good in all southern Turkey. The sequence photo was taken by Jukka Ruoskanen on a beach close to the town called Side in Turkey. Few minutes before totality high clouds came, and a halo was seen. The halo, of course, vanished with the sunlight and reappeared again after the total phase - the high clouds responsible for the halo can be seen in some of the photos. The sky colours were truly amazing with deep bluish hue towards the zenith and a great "sunset-like" appearence all over the horizon. The other noteworthy points were a significant temperature drop and the peculiar light some minutes before second contact. At that time the shadows were really sharp too.
The second (16 mm) wide-angle picture of the sky during the totality of the 2006 eclipse is taken by Günther Können in Colakli near Side at the south coast of Turkey, straight on the central line. The horizontal field of view is 135 degrees. At the 4 o'clock position fron the overexposed corona, Venus is visible. The limiting magnitude during totality is +3, about the same as during twiligt with the sun 7 degrees below horizon. The light of the sky occurs because of leaking of light via the horizon, from regions where the sun is not completely eclipsed.
4 comments:
Beautiful images! We were also near Side but to the east of the town. The thin clouds were to our west and (thankfully!) no halos were visible. Any high haze was quite thin. The sky at the zenith before second contact was a steely blue-dark grey that somehow made the almost pinpoint remnant of the sun whiter. Pre second contact shadows were noticeably sharper on one side but blurred on the other. The tops of shadows looked slightly reddened but I do not understand the reason.
Laurent Laveder was also near Side and has many eclipse images in his gallery (http://www.photoastronomique.net/)including one of the halo.
The 'black sun' could even be brighter than the sky a few degrees away because the Moon's disk is lit by earthlight. See http://www.digitalsky.org.uk/solar/tse-20060329/tse.html
The sequence photo of this posting and another one in here are genuine sequence photos taken with a fixed camera as multiple exposures into a single piece of slide film. The Sun path appears linearly descending in the photo because of gnomonic mapping function of a rectangular wide-angle lens (20mm lens in this case). To demonstrate this I quickly made a coordinate grid with Matlab and superimposed it with the original photo. The behaviour of the celestial coordinates seen through a wide angle lens can be seen here. The dots of the grid are separated by 5° in az and el directions. The grid also explains the appearence of the Sun path - the path does indeed reach the culmination point as expected, but due to mapping it can not be easily seen by just looking at the photo.
The difference in mapping functions of a rectilinear wide angle lens and a fisheye lens can be seen in the two attached photos of this posting. In the fisheye photo taken by Mr. Konnen the horizon is strongly curved whereas in the sequence photo it is more or less straight. The horizon remains as a straight line when using rectilinear wide angle lenses. In a fisheye projection the horizon gets strongly curved unless it is passing through the centerpoint of the photo.
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