Includes Autostar controller and deluxe field tripod
Cordless motor drive for fully automatic tracking
Equatorial fork mount, flip-mirror system
Maksutov meniscus corrector lens of Grade-A BK7 optical glass
Editorial Review:
Super popular Meade ETX-90AT Astronomical Telescope is one of the best Maksutov-Cassegrain 90mm telescopes available on the market today: For the casual or beginning observer the Meade ETX-90AT telescope may be all the telescope ever required. Or, for the advanced astronomer who already owns a larger instrument, the Meade ETX-90AT is the perfect ultra portable, diffraction-limited field telescope. Observe the continually changing cloud-belt patterns on the surface of the planet Jupiter; shadows cast on to Jupiter as one of its four principal satellites transits the planet's disc; the magnificent ring system and satellites of Saturn as well as dusky markings and the ring-shadow on the surface of Saturn; Moon craters by the hundred, plus lunar rilles, mountain ranges, and fault lines, all visible in brilliant, high-resolution, high-contrast detail; the variable phases of the planets Mercury and Venus; prominent features on the surface of Mars. With Meade ETX-90AT in deep-space the motivated observer will find it difficult to exhaust the quantity of visible phenomena: the incandescent filamentary structure of the Orion Nebula; the elliptical luminosity of the Andromeda Galaxy with its brilliant nucleus; the shining orb of the Hercules globular cluster with many of its outermost stars resolvable. These are only a few of the literally thousands of celestial objects within the view of the Meade ETX-90AT telescope. Star catalogs list innumerable double and multiple star systems, variable stars, open star clusters, globular clusters, diffuse nebulosities, planetary nebulae, and spiral galaxies within the grasp of the instrument. The optional Autostar Computer Controller can locate all of these objects automatically, in seconds.
The Meade ETX90EC is a compact telescope with excellent optics, packaged with a sturdy tripod and the remarkable Autostar computer control. Even though I own several telescopes and belong to an Astronomy club, the first night I took out the ETX, it showed me objects I'd never seen before. The ETX90EC is the computerized version of an affordable Maksutov-Cassegrain telescope first introduced by Meade in 1996. Every reviewer since then has commented on the excellent optics. How excellent? When I presented a session on optical testing at my local Astronomy club, I brought my ETX90 so that everyone could see what a "textbook" star test actually looks like.
What can you see with an ETX90? You won't see the flag on the Moon, but you will see sharp, color free views of mountains and valleys, craters, and lava flows. The planets are also a delight. I'll never forget seeing Saturn's rings with my own eyes for the first time. Although you can see the rings of Saturn and the cloud bands of Jupiter with the included 26mm Plossl eyepiece (about 48X magnification), you'll want to increase the magnification to bring out more detail. I find that a magnification of about 100X is ideal on most nights. You can reach 100X by using a Barlow Lens, I like the Celestron Ultima Barlow, or a smaller eyepiece such as the Celestron Omni Series 12.5mm . It's tempting to crank up the power to 200X or more, but on most nights I didn't see any more detail.
The Autostar controller makes it easy to find 30,000 celestial objects.
As good as the optics are, however, the most amazing feature of the ETX90EC is the Autostar computer. The ETX90EC with Autostar was the first computerized "go-to" telescope for under a thousand dollars. While bright objects like the moon are easy to find, the Autostar excels at finding the galaxies and star clusters that make space so fascinating. Maybe it's because I play with computers anyway, but I found the Autostar easy to use. The owners manual instructs you to begin the alignment by pointing the telescope North and tilting the telescope to level. I don't use a compass or a spirit level to do this, I simply point the telescope at the North Star, Polaris, and lower the telescope 44 degrees using the setting circles. This works because my home is near 44 degrees latitude. Don't know which star is Polaris? You'll want some kind of star chart that identifies the stars by name, NightWatch by Terence Dickinson is one of my favorites.
Many of the best galaxies and star clusters were discovered by a French comet hunter named Charles Messier. These so-called "M" objects looked to Messier like comets in the small telescopes of his day. My first night with the ETX, I switched on the "tour" mode. After looking at a few favorites, the cluster M52 came up on the Autostar. I pressed GO TO, and the telescope aimed itself at a cluster I hadn't looked at before. And darned if it didn't look just like a distant comet passing in front of a few small stars! I was so impressed, I bought an ETX for my step-son who works for the Air Force.
It's only fair to warn you, however, that if you find yourself enjoying astronomy, you may start wanting a bigger telescope! --Jeff Phillips
Pros:
Excellent optics
The Autostar computer finds objects and describes them for you
Small and easily portable
Cons:
It's small--the only way to see more detail is with a bigger telescope
When using small eyepieces, you might bump the finder scope with your nose
This telescope includes a free Autostar computer controller and deluxe field tripod with this ETX-90EC--a value of $349. And with the ETX-90EC, Meade brings a serious telescope into the price range of the casual consumer. The ETX-90EC Astro offers extraordinary optics at an affordable price. It combines a high-resolution optical design and diffraction-limited imaging with microprocessor-controlled, precise celestial-object tracking, all in a nicely styled, highly portable package. The Autostar controller turns the ETX-90EC into an automatic celestial-object locating system.
Catadioptrics
This is a catadioptric telescope. Catadioptrics use an ingenious combination of mirrors and lenses to "fold" the light path into a remarkably compact tube. This type of design--which includes Schmidt-Cassegrain and Maksutov-Cassegrain telescopes--offers good value even while it scores high on the techno-geek meter.
Read more about different telescope designs in our buying guide
Just plug the Autostar into the telescope's HBX port in place of the standard-equipment electronic controller, do a quick telescope alignment, and you're ready to observe any object in the Autostar's 30,000-object database.
The ETX-90EC also includes high-torque DC motors on both telescope axes, permitting electronic operation from the handheld controller. This pushbutton electronic controller has four dual-axis drive speeds: slow, 8x for image centering at high power; medium, 32x for image centering at lower power or for pushbutton tracking in altazimuth mode; moderate, 0.75 degrees per second for image centering in the viewfinder or for terrestrial tracking; and fast, 5 degrees per second for fast scanning across the sky.
The Meade ETX-90EC is specially designed to be portable and used in the field. It offers cordless operation, allowing you to use the telescope's dual-axis drive system for more than 40 hours on eight AA batteries. At approximately 8 pounds, and 15 inches in length, it packs a lot of power into a compact unit.
The ETX-90EC uses a 90mm Maksutov-Cassegrain optical design. Meade also uses EMC super-multicoatings on all optical surfaces to maximize light transmission through the corrector lens and reflectance from the primary and secondary mirrors. The flip-mirror system allows for 90-degree observation of land and sky objects, straight-through observation using the optional 45-degree erecting prism, or photo-ready imaging using the optional T-adapter and your own 35mm camera.
The Nuts and Bolts
1. Eyepiece 2. Viewfinder 3. Eyepiece Holder Thumbscrew - Tightens the eyepiece in place. 4. 90° Eyepiece Holder - Holds the eyepiece upright for easy viewing. 5. Optical Tube - The main optical component that gathers the light from distant objects and brings this light to a focus for examination with the eyepiece. 6. Vertical Lock - Controls the manual vertical movement of the telescope. 7. Fork Arms - Hold the optical tube in place. 8. Focus Knob - Moves the telescope's optical tube in a finely-controlled motion to achieve precise image focus. 9. Horizontal Lock - Controls the manual horizontal rotation of the telescope.
10. Computer Control Panel
A. ON/OFF Switch.
B. Auxiliary Ports - Provide connection for current and future Meade accessories.
C. Handbox (HBX) Port - for the Electronic Controller or the optional Autostar handbox.
D. The 12v connector, designed to accept an external power supply such as the optional AC Adapter or Power Cord.
E. LED power indicator light.
11. Base Housing - Supports the telescope for placement on a flat, level surface, such as a tabletop or optional tripod. 12. Holes for Optional Tripod - See your tripod's instruction sheet for mounting information. 13. Right Ascension (R.A.) Setting Circle. 14. Flip-Mirror and Flip-Mirror Control Knobs - ETX telescopes include an internal mirror. With the flipmirror control in the "up" position, light is diverted to the eyepiece. With the flipmirror control in the "down" position, as shown in Fig. 2b, light proceeds straight out the photo port for photography. 15. Photo Port - Attach any 35mm camera with a removable lens to this port using an optional adapter. 16. Declination Setting Circle (on left fork arm). 17. Viewfinder Alignment Screws - adjust these screws to align the viewfinder. 18. Viewfinder Alignment Bracket. 19. Dust Cap 20. Battery Compartment (not shown, underneath base).
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