Quote:
Originally Posted by Ryz
Barlow isn't stock with the Dob kit is it?
Think ive gotten the eyepiece holder/adapter confused with a Barlow...
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Some "starter" telescope kits come with just one eyepiece, some with two, some with two plus a Barlow, and some will give you a whole kit of eyepieces and filters etc - it really depends on what the manufacturer bundles, and what the reseller decides to "value add" to the deal. (Refractors and SCTs also come with a diagonal as well, but you don't need a diagonal with a Dob.)
The focuser / eyepiece holder stays permanently attached to the telescope tube, and racks in and out to focus the eyepiece when you turn the control knb. Eyepieces just slide into the focuser, and should be screwed in to make sure they don't shift or fall out.
The most common starter eyepieces would be typically 20 mm or 25 mm (low / moderate magnification) and 10 mm (higher magnification). The magnification you will achieve is equal to the focal length of the telescope (1200 mm for yours) divided by the focal length of the eyepiece, so a 20 mm eyepiece on your telescope will give you 60X magnification, while a 10 mm eyepiece will give you 120x.
A Barlow looks like a metal / plastic tube with a lens near the bottom of the tube (i.e. at the thinner end). It goes into the focuser, and then the eyepiece fits into the top end of the Barlow. A typical Barlow will be labelled "2x" (or sometimes "2.5x" or "3x"). It effectively multiplies the focal length of the telescope by the Barlow factor, so a 2x Barlow on your telescope makes it equivalent to a 2400 mm focal length, and a 20 mm eyepiece would give 120x magnification when used with a 2x Barlow.
Hope this helps!