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.

Available Immediately

All our equipment is currently on loan to other members.

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.

Orion Resolux 10.5x70 Astronomy Binoculars

Loan ends in 55 days on January 31, 2020 (Friday).

Resolux binoculars are our new favorite astro binoculars (and equally superb for long-distance daytime viewing), combining high-resolution, flat-field optics with rugged mechanical construction and the strict JTII spec for collimation. They are fully waterproof, and nitrogen purged to prevent internal lens fogging. The BAK-4 prisms and advanced multi-coatings on all optical surfaces really drink in the light. The eyepieces focus individually, and with 18mm or more of eye relief on each model, even eyeglass wearers will see the full field of view. The Resolux's all-metal housing is armored with thick rubber to ensure a secure, comfortable grip. Each binocular comes with tethered lens caps, heavy-duty tripod adapter, and neck strap.

These rugged 10.5-power Orion Resolux astronomical binoculars provide high-resolution views with a nice flat-field. Fully waterproof and nitrogen purged construction prevents lens fogging in damp conditions. High-quality BAK-4 prisms and advanced multi-coatings on all optical surfaces provide maximum light throughput for bright views rich in contrast. Orion's 10.5x70 Resolux binoculars are still hand holdable for short viewing sessions, and have a nice 5.0-degree field of view.

Orion StarMax 127 EQ

Loan ends in 55 days on January 31, 2020 (Friday).

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.

ZWO ASI120MC-S Imaging Camera

Currently there are 1 requests to borrow this.

ASI120S is a super speed and sensitive USB3.0 camera. Up to 60FPS under 1280X960 full resolution! With a peak QE of 75%, beyond ICX618 and with no FPN(Fixed pattern Noise)! Long time exposure supported up to 1000s! Full compatible with USB 2.0 USB Host!

Orion StarBlast 4.5

Currently there are 1 requests to borrow this.

The Orion StarBlast 4.5 EQ reflector telescope is suitable for beginner and intermediate astronomers. It comes with a sturdy EQ-1 equatorial tracking mount and adjustable-height tripod. Included are two eyepieces from the Orion Expanse series - a 15mm and 6mm - which have a large 66 degree apparent field of view. The included 15mm Expanse telescope eyepiece provides 30x power magnification, while the 6mm Expanse eyepiece bumps up the power all the way to 75x magnification.  An included Orion EZ Finder II reflex sight makes it easy to effectively aim the StarBlast 4.5 Equatorial Reflector Telescope anywhere in the night sky. The EZ Finder II projects a small red-dot onto a viewing window so all you have to do is move the telescope until the red-dot is aimed at the area of sky you wish to view through the telescope.

Celestron NexStar Evolution 6

Currently there are 4 requests to borrow this.

Celestron NexStar Evolution 6 includes integrated WiFi and can be controlled with your smartphone or tablet by connecting your device to NexStar Evolution’s built-in wireless network. A SkyAlign alignment procedure is built into the Celestron mobile app for setup of the "GoTo" mode that provides automatic slewing to a selected object. Use the planetarium interface to display a list of celestial objects currently visible based on your time and location. NexStar Evolution includes its own built-in battery and will operate for up to 10 hours on a single charge. Ergonomic handles help with setup. Manual clutches in both altitude and azimuth offer flexibility to manually point the telescope when powered off. The 6-inch NexStar Evolution tracking accuracy is accurate enough to get started in astroimaging by attaching your DSLR camera.

The telescope also includes a StarPointer finderscope, a 1.25” star diagonal, eyepieces, and an AC adapter.

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: