Corona - SOHO EIT composite

SOHO EIT 19.5 nm images (Fe XII) are very similar, from the structure point of view, to visible light images taken during an eclipse. It makes sense, because in the visible light, the green line 530.3 nm (Fe XIV) is very strong and may visualize nearly the same coronal structures as Fe XII line. Therefore I merged visible light images with SOHO EIT 19.5 nm image to visualize the part of corona hidden by the Moon. In order to make the image more understandable, I used 30.4 nm (He II) to show the layer laying under the coronal structures in 19.5 nm image (Fe XII). The He II image, I colored red-orange. It made the 3D understanding of the coronal structures nearly perfect. The only important information which is missing is the polarity of magnetic field - i.e. orientation of power-lines. This missing information can be found on the following image.
Click on the image or on the following reference to display the higher resolution image version (1.3 MB, PNG format).

Date08. 04. 2005
Time2nd contact 21:15:05 UT, 3rd contact 21:15:37 UT
SOHO EIT 19.5 nm image 21:23:37 UT
SOHO EIT 30.4 nm image 21:29:23 UT
PlacePacific ocean aboard the MV Galapagos Legend (about 2100 km west from the Galapagos)
Coordinate1° 19.554' S, 109° 30.190' W
ConditionsClear sky, altitude of the Sun above the horizon 60°
OpticsCanon 500mm f/4 IS lens
CameraCanon EOS 1Ds Mark II digital camera
Exposure1/2000 s - 1/15 s
ProcessingComposition of seven eclipse images and two SOHO EIT images. Eclipse images were aligned by means of phase correlation, calibrated and composed using a new, for this purpose newly developed, software LDIC 1.0, processed using Corona 3.0 in order to visualize coronal structures. Composition with SOHO images and the final processing was done using ACC 6.0 software.
Image processing by Miloslav Druckmüller
SoftwarePhaseCorr 3.0, LDIC 1.0, Corona 3.0, Sofo ACC 6.0 with Match II module
NoteFile names of used SOHO EIT images:
  efz20050408_212337 (19.5 nm Fe XII)
  efz20050408_212923 (30.4 nm He II)
OrientationThe image has the standard orientation i.e. North top, East left
More infoOriginal set of images
Copyright© 2005 Miloslav Druckmüller, Fred Espenak

Miloslav Druckmüller
Institute of Mathematics, Faculty of Mechanical Engineering
Brno University of Technology, Czech Republic
Page last update: 27.11.2019