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Equipment Library

The Seattle Astronomical Society maintains a library of small and medium size telescopes that may be checked out 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.

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Keywords

You can narrow your search of our equipment library by selecting any one of the below keywords.

Astrophotography Beginner Binoculars Camera Imaging Intermediate Maksutov Newtonian Refractor Schmidt Cassegrain Visual

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All our equipment is currently on loan to other members.

Available Eventually

The following list of equipment is currently loaned out to a member, and may include other members waiting to also borrow.

  • Planetary Imaging Kit

    Details

    Imaging

    Newly added 68 days ago on July 28, 2024 (Sunday).

    Currently there are 1 requests to borrow this.

    This kit includes a Canon XTi DSLR body and a ZWO ASI120MC-S  color CCD camera, a high quality Barlow lens, and adapters to attach either camera to a Schmidt-Cassegrain telescope. It works well with either of the Celestron 6 SE telescopes in the Loaner library.

  • ZWO SeeStar S50 Imaging Telescope #1

    Details

    Imaging

    Newly added 68 days ago on July 28, 2024 (Sunday).

    Currently there are 2 requests to borrow this.

    The Seestar S50 imaging telescope combines a built-in camera, tracking mount, focuser, and electronics into a compact unit that pairs with an app on your smartphone. It has four capture modes: Stargazing, Moon, Sun, and Scenery

All our equipment is in good condition!

Telescope Types

Types of telescopes

Copyright NIAAS, North Ireland Amatuer Astronomical Society

What are those numbers?

Types of telescopes

Copyright 2008-2012 Stormthecastle.com

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: