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Old 25-09-2017, 08:55 PM
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Peter Ward
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Peter Ward is offline
 
Join Date: Dec 2007
Location: The Shire
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Quote:
Originally Posted by Merlin66 View Post
I agree with the larger aperture, but slit spectroscopes need f10. They don't work effectively at faster f ratios...
Really? I used a SBIG self guiding spectrograph (18 micron slit) for about 12 months on a 14” F8 system. The spectrograph was somewhat immune to F ratio, (worked well at F6) but I found dispersion from the grating made aperture my friend.

TOTALLY off topic BTW.....
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