25 Foreside Road
Topsham, ME 04086
(207) 725-1727 

Sunday & Monday - Closed
Tuesday: 9am - 8pm
9am - 8pm
Thursday: 9am - 8pm
Friday: 9am - 5pm
Saturday: 9am - 4pm

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Marvel-Maine's Virtual Library

using barlow lens and star diagonal

Welcome to the Crooker Gallery!

Star Diagonal coupled with barlow
Nov 12, 2005 . Default Star Diagonal coupled with barlow. Will by placing a right angle star diagonal either before or after a 2x barlow lense alter the expected .

How to pick a barlow
A Barlow is an auxiliary lens system in a tube that mounts in front of the focal point . Barlow is used with a reflector, with a refractor used without a star diagonal, .

RASC Calgary Centre - Telescopes 5
May 4, 2007 . Telescopes Page 5 - Star Diagonals and Barlow Lenses . Light Paths in a telescope, with a Barlow Lens, and with a Star Diagonal Barlow .

How do I actually mount my Barlow lens in the telescope?
Aug 23, 2011 . A Barlow lens is a negative focal length lens that is used to increase the . (If you are using a star diagonal, the Barlow may protrude somewhat .

Crooker Gallery

Check the calendar or ask at the desk for future dates!

Coming next!

Joy of the Lens

Topsham Public Library
Juried Photography Exhibit

Meet Connie

Refracting Telescope :
Two Eyepieces 20mm, 8mm and a 2x Barlow lens. 3.90 degree Star diagonal. 4. Carry Bag. 5.Heavy duty Metal Field tripod with Altazimuth mount. 6.

                                         Artist Talk
Artist Talk

Eyepiece Adapter for Canon EF Lenses
The idea is to use a Canon EF telephoto lens (Canon EOS) for the optics, . Star diagonal with Barlow lens: To address the above focussing problem, you may .