Corona from Oregon

This image is a composition of 161 eclipse images acquired by means of two identical 800 mm lenses and two Nikon D810 cameras. The observing conditions were rather unique because of an absolutely perfect seeing. This enabled to create an image of extraordinary sharpness which is limited only by movement of coronal features during the total solar eclipse. Another result of perfect seeing and precise sub-pixel image alignment is visibility of faint stars below the 13th magnitude, some of them very near to the Sun. It was possible to visualize not only the solar corona but even the lunar surface surprisingly well. The position of the Moon is like that of 61 seconds after the second contact. The full resolution image may be found here.
Click on the image or on the following reference to display the higher resolution image version (2.7 MB, PNG format).

Date21. 08. 2017
Time2nd contact 17:21:11 UT, 3rd contact 17:23:14 UT
PlaceOregon near Mitchell, USA
CoordinateN 44° 31.539',   W 119° 54.459',  Alt. 1100 m
ConditionsClear sky but some smoke from forest fires, solar altitude 43° above horizon
Optics2× TS Photo Line Apochromatic Triplet D=115 mm, f = 800 mm with 2.5 inch flattener
Camera2×Nikon D810
Exposure1/1000 s - 1/4 s (camera 1), 1/4 s - 4 s (camera 2)
ProcessingComposition of 161 eclipse images taken with two cameras. Eclipse images were calibrated by means of dark frames and flat-fields, aligned by means of phase correlation, composed by means of LDIC 6.0 software, processed using Corona 5.0 in order to visualize coronal structures. Final processing was done using ACC 6.1 software.
Image processing by Miloslav Druckmüller
SoftwareAstro D3F 2.0, PhaseCorr 7.0, LDIC 6.0, Corona 5.0, Sofo ACC 6.1
OrientationImage must be rotated 18.02° anti-clockwise to achieve standard orientation i.e. solar North up.
Copyright© 2017 Miloslav Druckmüller, Peter Aniol, Shadia Habbal

Miloslav Druckmüller
Institute of Mathematics, Faculty of Mechanical Engineering
Brno University of Technology, Czech Republic
Page last update: 17.9.2017