Post on 20-Jan-2016
description
How To Buy Your First Telescope
Charlie Haffey
781-255-0229chaffey@norwood.k12.ma.uswww.norwood.k12.ma.us/sci
The Target User
Child
Adult
Beginner
Novice
What You Expect
http://antwrp.gsfc.nasa.gov/apod/ap050428.html
What You Get
http://antwrp.gsfc.nasa.gov/apod/ap050428.html
Types of Scopes
•Reflector
•Refractor
http://www.omni-optical.com/telescope/images/ut104-2scopes.gif
Reflector
http://www.omni-optical.com/telescope/images/ut104-2scopes.gif
Refractor
Types of Mounts
•Dobsonian
•Equatorial
Dobsonian
•Up and down
•Left and right
www.astrostuff.com/ Swift_Telescopes.htm
Equatorial mount
Rotates parallel to Earth’s axis
Easier tracking of objects
Magnification
http://www.celestron.com/tb-trms.htm
Focal Length
Calculate Magnification
Focal length of telescopeFocal length of eyepiece
1000 mm25 mm
= 40
Magnification Limits
•40x most common
•Increase magnification-•decrease field of view •decrease brightness
•Over 100x •rarely used•very difficult tracking
Image Brightness
Small increase in mirror diameter Large increase in surface area
6 inch mirror = 28 in2 area
8 inch mirror = 50 in2 area
Mr. Haffey Recommends
Six inch Dobsonian
$259 & up
The cheapest, easiest and best way
to improve your first telescope...
Zero magnification finder
EZ Finder™ II
Reflex Sight
$34.95
Upside is up finder
Right Angle
Correct-Image
Finder Scopes
$49.95 - $79.95
Do Not Buy
750 power!
From a deli
With unanswered questions
Do Buy
Largest opening you can afford
Move & use with comfort
Reputable source
Vendors
Orion Telescopes www.telescope.com
Meade Telescopes www.meade.com
Celestron Telescopes www.celestron.com
The Camera Company www.cameraco.com
866-769-0210
After you buy your first telescope
Contact Mr. Haffey
•First setup•First use•First light
Good Luck, Have Fun!