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

The following list of equipment is immediately available to borrow.

Edmund Astroscan

Loan ends in -69 days on April 30, 2020 (Thursday).

 

The Edmund Scientific Astroscan 4 1/8" Telescope comes in a basic package that includes the telescope, an open sight target finger, a cast-aluminum tabletop base that's padded to prevent scratches on sensitive surfaces, a user's manual, an eyepiece, and a carrying bag. The Astroscan has a three degree angle of view at 16X and makes a great beginner's scope requiring virtually no setup. It is very light-weight and perfect for small children.

NOTE: This telescope is permenately out of collimation and only works for low power viewing. 

AWB OneSky 130mm Reflector

Currently there are 1 requests to borrow this.

 

The AWB (Astronomers Without Borders) OneSky telescope is a 130 mm Newtonian reflector. It has a Dobsonian style mounting that is compact and intuitive to use. A red-dot reflex sight serves as a finder for aiming the scope. The truss tube telescope collapses into a compact size for storage and transport. Note that this telescope is designed to be placed on a small table or similar support when in use and does not come with a tripod.

Two eyepices are included. The low power eyepiece (25 mm focal length) provides 26 power and a wide, 2 degree true field of view for locating objects and for viewing large deep sky objects (star clusters, nebulae, and galaxies). The high power eyepiece (10mm focal length) provides 65 power for viewing the Moon, planets, and smaller deep sky objects.

This telescope is suitable for all ages and is a good choice for viewing the moon, planets, and bright deep sky objects. The red-dot finder is easy to use. However, you need to be able to see your target in the sky order to aim the scope accurately. In the city, a red-dot finder works well when aiming at the moon, planets, and bright stars. Finding faint deep sky objects generally requires dark sky unless, like the Great Orion Nebula, the object you are looking for is located near a bright star.

It is always good to set up a telescope away from any direct line of sight to porch lights or street lights, and this is especially important for an open truss tube  design like the AWB 130.

Specifications:
Aperture: 130 mm
Focal length: 650 mm (f/5)
Eyepieces: 25 mm (26x) and 10 mm (65x)
Tube length collapsed: 24 inches
Tube length collapsed: 14.5 inches
Telescope weight: 14 pounds

Celestron StarHopper 8

Currently there are 1 requests to borrow this.

 

This Celestron Star Hopper Dobsonian is an 8 inch Newtonian telescope on a Dobson style mount. Dobsonian telescopes are cost effective and provide good views of celestial objects.

Celestron NexStar 6 SE

Currently there are 4 requests to borrow this.

 

The Celestron 6 SE is a current model altazimuth 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. 

Tele Vue Eyepiece Set

Currently there are 4 requests to borrow this.

 

This set includes two older wide angle Tele Vue eyepieces (16mm and 9 mm) and two newer (13mm, 8mm) wide angle eyepieces.

Advanced CCD Astrophotography Kit with 80mm APO

Currently there are 5 requests to borrow this.

 

Note: This package requires the user to provide a laptop computer, install the necessary drivers, and polar align an equatorial mount.

This astrophotography kit is designed for imaging deep sky objects by capable amateur astronomers. It  includes a Meade Series 6000 APO ED APO (apochromatic) 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. The borrower should understand how to align and use an equatorial mount and must supply a laptop computer to operate the camera. The short effective focal length of the system allows unguided exposures of a few minutes, which can then be stacked during post processing 

The Meade Series 6000 80mm APO triplet refractor uses extra-low dispersion optical glass to provide excellent color correction, contrast, and sharpness.

Explore Scientific AR102mm Refractor

Currently there are 5 requests to borrow this.

 

The Explore Scientific AR Series telescopes are classic doublet achromatic f/6.5 refractors designed to provide low and medium magnification, wide field views of the sky. 

The Explore Scientific AR Series telescopes include 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-duty alt-azimuth mount and tripod designed to quickly and easily accept small to medium sized refractors.  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.

Celestron Echelon 16x70 Binoculars

Loan ends in 29 days on August 06, 2020 (Thursday).

 

Large-aperture astronomical binoculars are designed for viewing .star clusters, nebula, and galaxies. 16x magnification is sufficient to provide good views of many deep sky objects, It will provide pleasing views of the moon , and will show Jupiter and it's four Galilean moons. 

Celestron Echelon binoculars sport high quality 70 mm objective lenses made in Japan. BaK-4 prisms provide good contrast and sharpness, and all air-to-glass surfaces are multi-coated with Celestron’s proprietary XLT anti-reflection optical coatings.

 

Meade 8 LX200 EMC

Loan ends in 29 days on August 06, 2020 (Thursday).

 NOTE: This Telescope package is bulky and heavy and may not fit easily into smaller cars.

The Meade 8 LX200 EMC Schmidt-Cassegrain telescope is suitable for members experienced with medium to large sized computerized telescope. This telescope will give good views of the moon, planets as well as nebulae, star clusters and galaxies. However, it is an older design that is more complex to operate than newer telescopes and is not a good telescope for beginners.

Meade ETX-125EC

Currently there are 1 requests to borrow this.

 

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 SkyQuest XT10i

Currently there are 1 requests to borrow this.

Note: This is a heavy and bulky telescope.  It may require 2 people to lift it and a bigger vehicle to transport it.

The Orion SkyQuest XT10i IntelliScope Dobsonian Reflector features a fairly large 10" apperture mirror combined with the ease of use of a Dodsonian mount. The telescope includes altitude and azimuthal encoders and a computer controller for easy two start configuration and push-to navigation. With the Orion SkyQuest XT10i IntelliScope Computer Controller, the user can select an object to view from the controller's 14,000+ object database. A 9x50 finder scope is included to help aim the telescope. Three included telescope eyepieces, a 25mm, 17mm, and 9mm Sirius Plossl, provide you with views between 48x and 120x respectively. 

Orion Resolux 10.5x70 Astronomy Binoculars

Currently there are 2 requests to borrow this.

 

Large-aperture astronomical binoculars are intended for viewing star clusters, nebula, and galaxies. 10x magnification will provide good wide field views of larger deep sky objects such as the Great Orion Nebula and the Pleiades star cluster. At a dark sky site it will provide good views of Milky Way star fields and larger objects such as the Andromeda and Triangulum galaxies (M31 and M33). 

Like any binoculars, the Resolux 10.5x70 will provide pleasing views of the moon.

The Orion Resolux binoculars feature BAK-4 prisms and anti-reflection multi-coatings on all optical surfaces. The eyepieces focus individually and provide 18mm or more of eye relief They.have a 5.0-degree field of view.

A binocular tripod mount is provided in the SAS loaner package, but these 10.5x70 Resolux binoculars are hand holdable for short viewing sessions, especially if you can relax in a reclining lounge chair (not provided) while stargazing..  

Orion StarBlast 4.5

Currently there are 2 requests to borrow this.

 

The Orion StarBlast 4.5 EQ reflector telescope is suitable for beginner and intermediate astronomers. It comes with an equatorial tracking mount and adjustable-height tripod. Two eyepieces from the Orion Expanse series, which have a large 66 degree apparent field of view, are included. A 15mm Expanse eyepiece provides 30x power magnification, and a 6mm Expanse eyepiece provides 75x magnification.  An Orion EZ Finder II reflex sight is provided to 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 and the user must move the telescope until the red-dot is aimed at the intended area of the sky

ZWO ASI120MC-S Imaging Camera

Currently there are 2 requests to borrow this.

 

The ASI120MC-S is a color USB3.0 camera. primarily intended for planetary imaging, but it can be used for deep sky imaging with some limitations.

Orion StarMax 127 EQ

Currently there are 2 requests to borrow this.

 

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.  

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.

Celestron NexStar 8 GPS

Currently there are 2 requests to borrow this.

 

The NexStar 8  GPS is an 8-inch Schmidt-Cassegrain telescope with Celestron NexStar  computer control.

200 mm aperture, 2000 mm focal length

This is a heavy and bulky telescope.  It may require 2 people to lift it. Your vehicle must accomodate three large boxes (32x20x14, 24x18x12, and 30x10x10 inches) to transport it.  The optical tube assembly is about 45 lbs.  This is not a beginner telescope..

 

 

Sky-Watcher Star Adventurer Mini Tracking Mount

Currently there are 4 requests to borrow this.

 

Note: This equipment includes a small equatorial mount that must be carefully polar aligned and may be confusing for beginners.

Star Adventurer Mini is a high precision, portable and stable tracking platform for sidereal, solar and lunar tracking with automatic DSLR shutter release control. It is useful as a tracking platform to capture wide-field images of the Milky Way, or as a compact travel mount. The Equipment Manager can provide advice on setting up the equatorial mount.

A Star Adventurer Latitude Base is included and provides a smooth and reliable way to polar align your mount. With internal gearing the Latitude Base makes aligning to the north celestial pole easy and repeatable.  A MeFoto GlobeTrotter with a ball head is also provided.

Portable DSLR Astrophotography Kit

Currently there are 4 requests to borrow this.

 

Note: This equipment includes a small equatorial mount that must be carefully polar aligned and may be confusing for beginners.

This is a complete portable astrophotography kit which is suitable for wide-field astro-imaging.  The equipment includes a Sky-Watcher Star Adventurer equatorial tracking mount, Berlebach mini tripod, astronomy-modified Canon T3i with a 50mm and a 100mm lens, assorted cables, a Pelican case for the mount and camera, and a zipper bag for the tripod).  It comes with a manual to familiarize the user with the assembly, use, and care of the Star Adventurer equatorial tracking mount. The Equipment Manager can provide advice on setting up an equatorial mount.

Celestron NexStar Evolution 6

Currently there are 5 requests to borrow this.

 

The 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

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

Ultrastar Color Imaging Camera

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

This Ultrastar camera is being combined with a new telescope and mount to make a complete astrophotography loaner package. It will be available soon.

The camera and the required cables are included in this loaner. he user must supply a telescope, tracking mount and computer. The Ultrastar is an advanced version of Starlight Xpress 'Superstar' guide camera and it has a similar resolution of 1392 x 1040 pixels. However, the CCD chip has 70% more area and the QE is considerably greater, at around 75% peak. It is useful as both a guide camera and an imaging camera, which is especially well suited to 'Live Viewing' mode. A program called 'Lodestar Live' is capable of controlling the Ultrastar in Live view. It can also color convert and stack images from single-shots.

Coronado Personal Solar Telescope

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

This is not a beginner instrument. Please contact the Equipment Manager if you are interested in borrowing this H-Alpha Telescope.

The Coronado Personal Solar Telescope will show interesting details of the Sun, including sun spots and solar prominences,  Sunspots are not difficult to see,. However, both the focus and the H-alpha filter adjustments are critical.

Orion SkyQuest XT10g - Computerized GoTo Dobsonian

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

NOTE: This telescope is heavy and may require two adults to carry and set up.

The SkyQuest XT10g features GoTo pointing. It features a 254mm (10") aperture, 1200mm focal-length parabolic mirror (f/4.7).

Assembly is straightforward, but please note: This is a  very heavy and bulky telescope. The base is large and weighs nearly 40 lbs. The optical tube weighs 30 lbs and is about 12 inches in diameter by 48 inches long. It may require 2 people to lift it and a bigger vehicle to transport it. Handles on the Dobsonian base's front and side panels help to lift and carry the heavy base. Assembly is done by lifting the 30 lb. XT10g telescope optical tube into the Dobsonian base and locking it in place with a hand knob. A two-star alignment must be done to orient the telescope to the sky for GoTo operation. 

Our Orion SkyQuest XT10g GoTo Dobsonian Loaner Package includes an EZ Finder II reflex sight, three high quality eyepieces, and several useful accessories.

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

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