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.

Keywords

Equipment currently shown is filtered to only those tagged with Refractor

Available Immediately

The following list of equipment is immediately available to borrow.

Explore Scientific AR102mm Refractor

Currently there are 2 requests to borrow this.

The Explore Scientific AR Series telescopes are classic air-spaced, crown-and-flint, doublet achromatic f/6.5 refractors with a superior-class optical figure.

The Explore Scientific AR Series telescopes come with heavy-duty, high quality components, including a 2" dual-speed Crayford-style focuser, a one-piece 2" diagonal with 99% dielectric coatings, an 8 X 50 non-illuminated straight -thru finderscope and quick release bracket, and a cradle ring assembly with Vixen-style dovetail mount.

A Twilight I mount is included. The Twilight I is a light-to-medium-duty alt-azimuth mount and tripod designed to quickly and easily accept small to medium sized refractors. The adjustable angle head can be tilted forward or back at a 45° angle to allow more clearance for your telescope so you can point it straight up for viewing at the zenith. Slow-motion control cables are attached on the vertical and horizontal axes, and are easy to turn during the night.

Available Soon

Available Eventually

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

Advanced Astrophotography Kit - Meade 80mm Refractor

Currently there are 4 requests to borrow this.

This advanced astrophotography kit includes a Meade Series 6000 APO ED APO 80mm refractor, a Celestron Advanced VX telescope mount, a ZWO ASI294MC Pro cooled camera with a reducer/flattener, and all the necessary cables and power supply.  It comes with all the pertinent manuals to use the various gear.  This astrophotography kit is designed for imaging deep sky objects.

The Meade Series 6000 80mm APO triplet refractor is built with the observer and imager in mind.  With the three element optical design using the highest grade extra-low dispersion optical glass, false color is virtually eliminated, yielding astonishing color correction, contrast, and sharpness.

Currently Unavailable

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

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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: