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Old 24-06-2015, 12:39 PM
N1 (Mirko)
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Join Date: Oct 2013
Location: Dunners Nu Zulland
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Quote:
Originally Posted by Alasdair View Post
And as possibly a very foolish beginners question, say I was looking at Saturn with the highest usable magnification on an 8" dob - how long would it remain in the field of view,
That is a more than reasonable question. I observed Saturn through an 8" GSO dob at the stupidly high power of 480 the other night. Saturn took about 25 seconds to cross the XO 2.5's 44° AFOV. I had never intended to use this eyepiece on a dob like that (too narrow, too much power) but thought stuff it I'll give it a go. Neither concern materialised. Saturn is a forgiving target though.

Quote:
Originally Posted by Alasdair View Post
and how easy is it to hand track such an object for visual observing?
That's highly subjective, so I might as well say it's easy because it is for me. Assuming the bearings don't stick or grind of course. Less power (no more than 400x recommended for 8"), or more apparent field of view than above, and it becomes even easier. The general consensus is to use as wide an eyepiece (AFOV) as possible for Hi power on a dob to minimise nudging, but that doesn't mean other eyepieces such as modern orthos won't do well.
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