View Single Post
Old July 23, 2006, 12:34 PM   #8
Capt. Charlie
Moderator Emeritus
 
Join Date: March 24, 2005
Location: Steubenville, OH
Posts: 4,446
DNZ, your link is to a refractor telescope. These use lenses only in a straight line to magnify an image (same as conventional spotting scopes). You want a reflector 'scope (short, wide barrel) which uses ground mirrors along with lenses. Reflectors are much brighter.

Quote:
I am guessing that the 3X Barlow lens will triple the eye piece?
Correct, but Barlow lenses also cut down the amount of light transmitted and magnify any aberrations in the eyepiece. Better to use an eyepiece only, if you can, and if you must use a Barlow, use a 2X.

Quote:
They look to be mounted for upward sky viewing angles? And are there complications with reverse images that need to be corrected with a special part? Is there a problem of too much light when using these in bright day conditions at the range?
Scopes with the eyepiece mounted at 90 degrees are designed for astronomy, and they are a little awkward for range use, and yes, image reversal can be a problem, but most of those designed for use as a spotting scope have the eyepiece mounted at 45 degrees, and have no image reversal. Being too bright isn't a problem unless you happen to cross paths with the sun, and that would result in instant blindness with any scope.

I have a Meade ETX-90-EC. It doubles as both a spotting scope, and an astronomy telescope. You can mount the eyepiece on top at 90 degrees, or on the back at 45 degrees for a spotting scope. The 45 degree mount also corrects the image reversal. The ETX-90 would cost you considerably more than $200. though.

Whichever scope you decide on, I strongly suggest you make sure it uses the Maksutov-Cassegrain optical system. This is what makes all the difference, in quality, and in price.
__________________
TFL Members are ambassadors to the world for firearm owners. What kind of ambassador does your post make you?

I train in earnest, to do the things that I pray in earnest, I'll never have to do.

--Capt. Charlie
Capt. Charlie is offline  
 
Page generated in 0.03268 seconds with 8 queries