Sun through Coronado H-alpha filters
Updated : 28 August 2005.
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CCD : Canon 20D Hutech mod
Exposure time : 1/125 s
Date and Time : 28. August 2005, 15:52 UT
Instrument : FSQ @ f/13 (SM90)
Focal length : ca. 1200 mm (2x Powermate)
FWHM : about 0.07 nm (single H-alpha filters)
Filters : Baader UV-IR filter
Image processing : Photoshop
Problems/comments : Further processing in Imageplus (grading) and Photoshop (unscharp mask, levels, curves, combination, colorized). Best image out many images graded with Imageplus V2.75. Imaged at my backyard between clouds, Mol, Belgium.