Author Topic: Winter Solstice with the 17-55 and a surprise  (Read 1649 times)

Bjørn Rørslett

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Winter Solstice with the 17-55 and a surprise
« on: June 27, 2015, 00:56:46 »
[ Posted 21 December 2007 - 21:13 Modified and reposted by agreement ]

Winter solstice occurs of course every year so isn't normally that exciting. In my country, we barely see the solar disc above the horizon these days. The last days have had very cold weather even for this time of the year, and the cold air is trapped by the hill range encircling the inner Oslo Fjord. The accompanying temperature inversion generates ice-crystal fog and all sorts of refractive phenomena.

Here is a parhelion at Winter Solstice with a associated sun pilar (not clearly seen due to my low vantage point) and a Moilanen Arc 11 degrees above the setting sun. A Moilanen Arc manifests itself as a V-shaped coloured pattern with the apex pointing towards the sun itself.

This refractive phenomenon is very rare and can only occur when the solar angle is low in conjunction with fog close to the ground and ice crystals are present in the air. No satisfactory scientific explanation of this V-shaped pattern exists.

Shot with the 17-55/2.8 Nikkor DX and the Nikon D300 which was the gear I had with me at the time. The lens itself has no field curvature.



Here is another shot of the Moilanen Arc at Winter solstice. The foreground subject in fact is my own house, and I shot using autofocus on the D300. Again, no field curvature, and perfect focus.



The 'banding' just barely seen in the first image Actually it is frost fog that is breaking up.  My vantage point was almost at the top of the frost layer.

Blue hues and freezing cold go hand in hand. The Kelvin temperature is around 20000 or so. The camera responds to that.  I, the photographer, respond to -15C with high humidity by snapping the shutter as fast as possible, then seek indoor shelter (I'm living near the Oslo Fjord, so the climate in winter has a maritime influence and tends not to get very cold but at the same time, quite humid).