Equipment Library
The Seattle Astronomical Society maintains a library of small and medium size telescopes that may be checked out for a period of 1 month by members in good standing. If you are new to astronomy, this is an excellent way to learn how to use a telescope and to begin viewing the wonders of the night sky, without having to invest immediately in a telescope of your own. To check out a telescope, please check out our equipment available for loan.
If you have any questions about borrowing equipment, or do not see a specific piece of equipment please reach out to our Equipment Manager.
See the complete equipment list in alphabetical order.
Keywords
You can narrow your search of our equipment library by selecting any one of the below keywords.
Astrophotography Beginner Binoculars Camera Intermediate Maksutov Newtonian Refractor Schmidt Cassegrain Visual
Search
All our equipment is currently on loan to other members.
Available Soon
The following list of equipment is currently loaned out, loan ends in the next two weeks, and no one else has requested to borrow it. This is a great time to request to borrow it!
-
Celestron NexStar 6 SE
Currently there are 4 requests to borrow this.
Six Inch Computer Controlled (GoTo) Schmidt-Cass Telescope (SCT)
The Celestron 6 SE is a current model computerized Schmidt-Cassegrain telescope. The 6 SE features a relatively long 1500mm focal length (f/10) and a total weight of 30 lbs including the tripod.
-
Orion StarMax 127 EQ
Currently there are 3 requests to borrow this.
Currently assigned to the SAS Outreach Team
5 Inch (127 mm) Maksutov-Cassegrain Telescope with Equatorial Mount.
Request queue is long. Contact the Equipment Manager for an estimated availability date.
The StarMax 127 telescope has a long focal length and is ideal for observation of the moon, planets, and double stars. The equatorial mount makes it easier to track the moon and planets at high magnification, but can be confusing for beginners.
Available Eventually
The following list of equipment is currently loaned out to a member, and may include other members waiting to also borrow.
-
Celestron 102mm f/10 Equatorial Refractor
Newly added 34 days ago on July 04, 2022 (Monday).
Currently there are 2 requests to borrow this.
The Celestron C102 is a 102mm aperature, achromatic refractor with a sturdy XLT equatorial mount.. The long f/10 focal ratio provides a sharp image and is ideal for viewing planets, the moon, and bright deep sky objects.
Available by Request
Contact the Equipment Manager for more information on borrowing the following equipment.
-
Meade ETX-125 (#1)
Special Item: Contact the Equipment Manager to borrow this older telescope
5 Inch (125 mm) Maksutov-Cassegrain GoTo Telescope
This is an older computer controlled telescope. Optical quality is very good but mechanical quality is not as good as newer telescopes. The GoTo setup procedure must be followed exactly. Beginners may need assistance.
The Meade ETX-125EC telescope is a Maksutov-Cassegrain design that folds a relatively long focal length into a relatively short optical tube. The long focal length makes it easy to reach high magnification for observation of the moon and planets. The Meade AutoStar controller provides Go-To operation, but AutoStar is an older generation. Setup involves several steps that may be confusing for beginners,
Telescope Types
What are those numbers?
The f-ratio is the focal length divided by the diameter of the telescope. Magnification is the focal length of the telescope divided by the focal length of the eyepiece.
Example
To find the f-ratio of a telescope 10 " in diameter with a 45" focal length:
Divide 45 " F.L. by10" D. to get an f-ratio of 4.5.
Compute Magnification
First, convert focal length to mm: 45" = 1146 mm, then:
1146 mm focal length divided by 35 mm eyepiece equals 33 magnification.
More Information
If you are interested in learning more about telescopes, we recommend:
- SAS member Sorin (aka Soggy Astronomer ) has written an article, The Agony of Buying Your First Telescope and also presented at our May 15, 2013 general meeting, which includes additional information and links.
- Sky & Telescope's excellent article on equipment basics
- North Ireland's Choosing A Telescope by Andrew Johnston