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Old 09-06-2009, 12:36 AM
ColHut (Colin)
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ColHut is offline
 
Join Date: Jul 2006
Location: Perth WA
Posts: 269
Eyepiece advice for fast Newts

I saw this posted here and wondered what users thought.
(http://www.astromart.com/articles/ar...?article_id=50)

Let’s say you have an excellent fast Newtonian, but you’re stuck with eyepieces that don’t work well with it. You can’t afford a Paracor and all-new premium wide-angle eyepieces. What to do? I’d suggest getting a high quality Barlow lens that multiplies about 1.5-1.8X. This will both increase the power your present eyepieces deliver, but it’ll also radically reduce the astigmatism you see near the edge of their fields, because your eyepieces will be working with a shallower light cone. And, now that you’re effectively using a longer-EFL telescope, you can ad something like a 35- to 40-mm wide angle eyepiece to get back the lowest power you lost when you added the Barlow.

regards
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