Baily's Beads on Second Contact

The main problem of solar eclipse photography is the enormous contrast. Baily's beads (photosphere) to corona have brightness ratio over 1 000 000 : 1. It is obvious that neither film nor digital camera are able to manage this contrast. The only way how to obtain an image similar to that you may see during the eclipse is to use composition techniques and adaptive filters. This image was created using one image of Baily's beads taken near the second contact and eight more images with longer expositions processed by means of adaptive kernel convolution in order to suppress high contrast and enhance fine coronal structures.

Date 21. 06. 2001
TimeSecond contact 12:36:34 UT, third contact 12:41:10 UT
Total eclipse duration 4 min 36 s
PlaceAngola, near Sumbe (Ngunza)
CoordinateS 11° 07' 29'', E 13° 55' 51'', Alt. 168 m
ConditionsExcellent, clear sky
OpticsMertz - II, 1875/100 mm (VOD Turnov), siderostat off-axis configuration
CameraPENTAX 67 II, 6 × 7.5 cm format
Resolution2.217 arc sec / pixel (image presented on this page)
FilmKodak Ektachrome 100 S Professional
ProcessingComposite of 9 images enhanced by means of adaptive kernel convolution
Image processing by Miloslav Druckmüller
ScannerNikon LS 8000 (4000dpi resolution, RGB, 3 × 16 bit/pixel)
SoftwareSofo ACC 5.0 Scientific Image Analyzer with Match II Module (final processing)
Corona 2.0 Analyzer (coronal structure enhancement)
PhaseCorr 2.0 Analyzer (rotation estimation - registration of images)
OrientationImage must be rotated -9.47° (clockwise) to achieve standard orientation (N top, E left)
Copyright© 2001 Úpice Observatory, © 2003 Miloslav Druckmüller


Miloslav Druckmüller
Institute of Mathematics, Faculty of Mechanical Engineering
Brno University of Technology, Czech Republic
Page last update: 19.3.2007