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Old 26-10-2012, 03:43 PM
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Merlin66 (Ken)
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Join Date: Oct 2005
Location: Junortoun Vic
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Greg,
I depends on the resolution required and the acceptable SNR....
But, I'd say around +13mag maybe close.....
(A slitless grating ie Star Analyser/ Rainbow Optics, which has very low resolution R=100/200 would get you a little further. The issue/problem would/could be background stars/ galaxy contaminating the spectrum..)
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