Thread: Prom on the Sun
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Old 04-08-2014, 01:46 PM
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Merlin66 (Ken)
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Join Date: Oct 2005
Location: Junortoun Vic
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Peter,
John is using an external Ha etalon filter.
These are pretty expensive, sophisticated filters. Specifically for viewing the sun in Ha wavelengths - to show the surface detail, filaments and prominences.
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