Parhelion.jpg displays one of the parhelions which could be noticed
several times per week in summer 2001. The series Parhelion2.jpg
to Parhelion8.jpg was taken in winter 2002/3 and also at 12/17/2003.
The parhelions mostly occur in stratiform Cirrus clouds as shown
in this series. Alternatively they arise in aged and therefore
broadened and layered contrails.
Parhelion9.jpg and Parhelion10.jpg were recorded during the flight
from Frankfurt to Birmingham at an altitude of 11 km above the
British Channel. The Cirrus clouds which the aircraft passed were
barely larger than the aircraft itself. They consisted of extremely
thin, small cloud frazzles, which were almost invisible from the
aircraft. They could only be recognized because of short "twinkling"
of the diffraction effects.
According to this it was difficult to take a picture. The bright
spots on the images are scratches and stains on the window glass
in the back light.
Parhelion11.jpg was also taken from an airliner at cruising altitude.
However the parhelion was visible for a longer period of time
Optical Effect: Parhelions occur
as elucidation mostly of the 22 degree halos at the same altitude
as the sun if it is at a low angle. If the sun stands higher above
the horizon the parhelions are found at angles larger than 22
degrees. This is caused by the refraction of the light at the
hexagonal small ice platelets (not at the columns) within the
Cirrus Clouds. Thereby the small platelets have to be aligned
in a way that their basis (the largest ice surface) is coplanar
to the earth surface. The clearer the air is the brighter the
appearance of the parhelions.
Parhelion.jpg: S. Borrmann, Ingelheim, Germany, July 2001
Parhelion2-4.jpg: S. Borrmann, Pulpit Rock, Carinthia, 4 January
2003 around 3 p.m.
Parhelion5-8.jpg: S. Borrmann, Frankfurt Airport, 17 December
2003 between 2:27 and 2:32 p.m.
Parhelion9+10.jpg: S. Borrmann, flight from Frankfurt to Birmingham,
17 December 2003
Parhelion11.jpg: S. Borrmann, flight from Frankfurt to Philadelphia,
6 December 2004 at 1:38 p.m.
Olympus E-1 SLR 14-54 mm objective. Exposure and
sensitivity choice was not automatically performed by the camera.
In order to achieve possibly short time of exposures, the images
were taken with a fix lens aperture and a sensitivity of 400 ASA
in a sRGB colour range at a resolution of 2560 x 1920 Pixel x