Image

Inner Corona Structure (version 2)

Decrease of coronal structures contrast with the increasing distance from the Sun is a typical property of the solar corona. As the sky is relatively bright during the total solar eclipse the decrease of contrast is much bigger than in the reality. This contrast decrease can be at least partially compensated by mathematical processing. This method was used for image processing of this image. Compare it with version 1 of corona image on which the compensation was not done.
 
Click on the image or on the following reference to display the higher resolution image version (2.2 MB, PNG format).

ImageSe2001u_comp09-17_enh2.png
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
Resolution4.434 arc sec / pixel - full resolution version
FilmKodak Ektachrome 100 S Professional
ProcessingSum of 8 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 the 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
druckmuller@fme.vutbr.cz
Page last update: 19.3.2007