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

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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 .
http://www.bautforum.com/showthread.php/34782-Star-Diagonal-coupled-with-barlow

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, .
http://www.astronomics.com/main/category.asp/catalog_name/Astronomics/category_name/8M71WR24K8K48LAX1LJ4J9WXK7/Page/1

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 .
http://calgary.rasc.ca/telescopes/page5.htm

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 .
http://www.celestron.com/c3/support3/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=2527

Crooker Gallery


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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.
http://www.galileotelescope.com/nf/indrfr.htm



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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 .
http://www.iscap.columbia.edu/jank/Photo/Info/Eyepiece_Adapter/index.html