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.

All our equipment is currently on loan to other members.

None of our equipment is loaned out to any members.

Currently Unavailable

The following list of equipment is not available to members until we are able to replace or repair parts.

Meade ETX-125EC

Note  This item is being serviced and it is not available for check out.

 

There is a waitlist for this equipment. New requests to borrow it are not being accepted until spring 2021.

The Meade ETX-125EC telescope is a Maksutov-Cassegrain design that folds a relatively long focal length into a relatively short and easy to handle optical tube. The long focal length makes it easy to reach high magnification for observation of the moon and planets. The 125 mm aperature is large enough for nice views of brighter deep sky objects. The Meade AutoStar controller provides Go-To operation (Note that this AutoStar computer is an older generation and setup takes a bit of time, but it works fine for viewing the moon, the planets, and some brighter, easier to locate deep sky objects.)

Orion StarMax 127 EQ

Note  This item is being serviced and it is not available for check out.

 

There is a waitlist for this equipment. New requests to borrow it are not being accepted until spring 2021.

Note: This equipment includes an equatorial mount that must be set up properly. For visual use, just point the polar axis of the mount approximately toward the  north star.  

The StarMax 127 telescope is a Maksutov-Cassegrain design that folds a long focal length into a relatively short and easy to handle optical tube. The long focal length (1540mm) makes it easy to reach high magnification for observation of the moon and planets. The 127 mm aperature is large enough for nice views of brighter deep sky objects.  Includes an adjustable tripod and equatorial mount with manual slow-motion controls. The equatorial makes it easier to track the moon and planets at high magnification, but can be confusing for beginners. The Equipment Manager can provide advice on setting up and using an equatorial mount.

Telescope Types

Types of telescopes

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What are those numbers?

Types of telescopes

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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: