Eclipse image composed with SOHO LASCO C3

The resulting wide-angle eclipse image visualizes the corona with acceptable contrast up to nearly 20 solar radii. The next logical step was to compose the Earth-based image with the SOHO LASCO C3 coronograph image. The bright points in the resulting images are stars. The original image contains not only stars, but also impulse noise. This impulse noise was filtered out. In order to preserve stars, it was necessary to identify them before the filtering procedure. It was done by aligning and comparing two different SOHO images.
Click on the image or on the following reference to display the higher resolution image version (551 KB, PNG format).

Date01. 08. 2008
Time2nd contact 11:03:35 UT, 3rd contact 11:05:39 UT
Total eclipse duration 2 m 4 s
PlaceMongolia, Bor Udzuur
Coordinate45° 43.251' N, 92° 06.837' E, 1223 m altitude
ConditionsExcellent - clear sky, altitude of the Sun above the horizon 22°
OpticsCanon 2.8/70-200 mm L set to 200 mm (Canon EOS 5D)
Maksutov-Cassegarin 3M-6A, 6.3/500 mm (Canon EOS 350D)
CameraCanon EOS 5D (Hutech Ia modification) (ISO 100 and 200)
Canon EOS 350D digital camera (ISO 100)
Exposure1/125 s - 8 s
ProcessingComposition of 55 eclipse images (23 Canon EOS 5D, 22 Canon EOS 350D) and SOHO LASCO C3 image. Eclipse images calibrated by means of dark frames and flat-fields, aligned by means of phase correlation, composed by means of LDIC 5.0 software, processed using Corona 4.1 in order to visualize coronal structures. Final processing was done using ACC 6.1 software.
Image processing by Miloslav Druckmüller
SoftwareAstro D3F 2.0, LDIC 5.0, Corona 4.1, Sofo ACC 6.1
NoteSOHO C3 was image taken at 11:18 UT
OrientationImage has standard orientation i. e. North up.
Copyright© 2008 Miloslav Druckmüller, Peter Aniol, Vojtech Rušin

Miloslav Druckmüller
Institute of Mathematics, Faculty of Mechanical Engineering
Brno University of Technology, Czech Republic
Page last update: 19.3.2009