Knowledge Base

Features of this Telescope's Optical System . . .

• Oversized primary mirror: The 7" LX200GPS Maksutov has a Pyrex aspheric primary mirror 8.25" in diameter, over an inch larger than the 7" corrector lens at the front of its optical tube that admits the light. Due to the Maksutov design, the meniscus corrector causes the incoming light to diverge as it travels from corrector to primary mirror. If the primary were not oversized, almost 30% of the incoming light would be lost. Despite the 8" diameter of the primary mirror, the 7" diameter of the corrector still determines the aperture of the scope, making this Maksutov a true 7" telescope.

• Meniscus corrector lens: The double-sided spherical meniscus correcting lens is manufactured of Grade-A crown BK7 optical glass and is free of the striations and imperfections that could otherwise degrade optical performance. The BK7 glass provides increased IR and UV transmission for scientific measurement purposes.

• Fully multicoated UHTC (Ultra High Transmission Coatings) optics: The primary and secondary mirrors are vacuum-coated with aluminum, enhanced with multiple layers of titanium dioxide and silicon dioxide for increased reflectivity. These multicoatings are then overcoated with a protective layer of silicon monoxide (quartz) for long life.
      A series of anti-reflective coatings of aluminum oxide, titanium dioxide, and magnesium fluoride are vacuum-deposited on both sides of the BK7 meniscus corrector to provide a high 99.8% light transmission per surface, versus a per-surface transmission of 98.7% for standard single-layer coatings. Overall light throughput (the amount of light collected by the objective lens that actually reaches your eye or camera) is approximately 89% at the Cassegrain focus.
      UHTC multicoatings provide a 15% increase in light throughput (the amount of light collected by the objective lens that actually reaches your eye or camera), when compared with standard coatings. They effectively add the equivalent of an extra half inch of light-gathering aperture to the performance of the 7" scope with standard coatings, but with no increase in actual size or weight. They also improve contrast, for lunar and planetary images that appear sharper and more crisply defined.

• Fully baffled optics: A conical baffle attached to the correcting lens around the secondary mirror spot, in combination with the cylindrical baffle tube projecting from the primary mirror, prevents stray off-axis light from reaching the image plane. In addition, a series of field stops machined into the inner surface of the central baffle tube effectively eliminates undesirable light which might reflect from the inside surface of the baffle tube. The result of these baffle systems is extremely high-contrast images observed against an unusually dark background in lunar, planetary, and deep space observing alike.

• Built-in optics cooling fan: Because the large primary mirror and the thick corrector lens retain heat when you first take the scope outside during cool Fall or Winter nights, a thermal stabilization (cooling) fan is built into the rear cell of the scope. It drastically reduces the time needed to cool the scope optics down to their optimum operating temperature.

• Mirror lock: A progressive tension lock knob on the rear cell locks the telescope's primary mirror rigidly in place once an approximate manual focus has been achieved. The standard equipment electric focuser, described below, is then used for fine focusing. Locking the mirror eliminates the possibility of mirror shift (the image moving from side to side while focusing, caused by the primary mirror tilting on the central baffle tube as the mirror moves fore and aft along the tube). Mirror shift, once the bane of CCD astrophotographers because it could easily move a planetary image off a small CCD chip, is non-existent with the Meade system.

• Electric focuser: The supplied zero image-shift electric microfocuser is controlled by the Autostar II computer hand control. It moves an externally-mounted eyepiece or camera to focus, rather than moving the primary mirror. This eliminates mirror shift during precise image centering and focusing. The microfocuser has four different operating speeds, from very fast down to an extremely slow creep, giving you focusing accuracy to a truly microscopic level during critical visual and astrophotographic applications.
      The focuser is designed to hold 2" star diagonals and eyepieces. A supplied 1.25" adapter allows the use of 1.25" diagonals and eyepieces in the 2" focuser. Another supplied adapter duplicates the 2" rear cell thread used on Schmidt-Cassegrain telescopes to allow the use of off-axis guiders, T-adapters, etc. A 1.25" visual back is not supplied with the scope. If you want to do high magnification eyepiece projection photography of the Moon and planets, you will have to add an optional 1.25" visual back #9135 and a tele-extender to the focuser's supplied 2" rear cell thread adapter.

Features of this Telescope's Schmidt-Cassegrain Optical System . . .

• Oversized primary mirror: The diameter of the primary mirror of each LX90 LNT is larger than the diameter of the Schmidt corrector lens at the front of its optical tube that admits the light. The primary mirror of the 8" scope is actually 8.25" in diameter, compared to the 8" diameter of the corrector lens. The 10" primary is 10.375" in diameter, and the 12" primary is 12.375". Oversizing the primary mirror in this way gives you a wider fully-illuminated field than a conventional SCT whose corrector and primary mirror are the same size. The result is a gain of 5% to 8% more off-axis light available to your eye or camera, depending on the telescope.

• Fully coated optics: The Pyrex primary and secondary mirrors are vacuum-coated with a thin layer of aluminum that provides approximately 89% reflectivity per surface. Once aluminized, the mirrors are overcoated with a protective layer of silicon monoxide (quartz) for long life.
      A thin layer of anti-reflection magnesium fluoride is vacuum deposited on both sides of the water-white float glass Schmidt corrector plate to provide a high 98.7% light transmission per surface, compared to the 96% transmission of uncoated glass. Overall light throughput (the amount of light collected by the objective lens that actually reaches your eye or camera) is approximately 77% at the Cassegrain focus.
      For those interested in even more brightness for photography and observing faint deep space objects, Meade also offers this scope with optional UHTC (Ultra High Transmission Coatings) for a 15% increase in light throughput. Optional UHTC multicoatings effectively add the equivalent of extra light-gathering aperture to the performance of a scope with standard coatings (the equivalent of three-quarters of an inch of extra aperture in the case of a 10" scope, for example), but with no increase in actual size or weight.

• Fully baffled optics: A cylindrical baffle around the secondary mirror, in combination with the cylindrical baffle tube projecting from the primary mirror, prevents stray off-axis light from reaching the image plane. In addition, a series of field stops machined into the inner surface of the central baffle tube effectively eliminates undesirable light which might reflect from the inside surface of the baffle tube. The result of these baffle systems is improved contrast in lunar, planetary, and deep space observing alike.

Features of this Telescope's Schmidt-Cassegrain Optical System . . .

• Oversized primary mirror: The diameter of the primary mirror of each LX90LNT is larger than the diameter of the Schmidt corrector lens at the front of its optical tube that admits the light. The primary mirror of the 8" scope is actually 8.25" in diameter, compared to the 8" diameter of the corrector lens. The 10" primary is 10.375" in diameter, and the 12" primary is 12.375". Oversizing the primary mirror in this way gives you a wider fully-illuminated field than a conventional SCT whose corrector and primary mirror are the same size. The result is a gain of 5% to 8% more off-axis light available to your eye or camera, depending on the telescope.

• Fully-multicoated UHTC (Ultra High Transmission Coatings) optics: The Pyrex primary and secondary mirrors are vacuum-coated with aluminum, enhanced with multiple layers of titanium dioxide and silicon dioxide for increased reflectivity. These multicoatings are then overcoated with a protective layer of silicon monoxide (quartz) for long life.
      A series of anti-reflective coatings of aluminum oxide, titanium dioxide, and magnesium fluoride are vacuum-deposited on both sides of the water-white float glass Schmidt corrector plate. These antireflection multicoatings provide a high 99.8% light transmission per surface, versus a per-surface transmission of 98.7% for standard single-layer coatings. Overall light throughput (the amount of light collected by the objective lens that actually reaches your eye or camera) is approximately 89% at the Cassegrain focus.
      UHTC multicoatings provide a 15% increase in light throughput (the amount of light collected by the objective lens that actually reaches your eye or camera), when compared with standard coatings. They effectively add the equivalent of six-tenths of an inch of extra light-gathering aperture to the performance of the 8" scope with standard coatings, the equivalent of three-quarters of an inch of aperture to the 10" scope, and the equivalent of 0.85" of extra aperture to the 12" scope - but with no increase in size or weight. The UHTC multicoatings also improve contrast, for lunar and planetary images that appear sharper and more crisply defined.

• Fully baffled optics: A cylindrical baffle around the secondary mirror, in combination with the cylindrical baffle tube projecting from the primary mirror, prevents stray off-axis light from reaching the image plane. In addition, a series of field stops machined into the inner surface of the central baffle tube effectively eliminates undesirable light which might reflect from the inside surface of the baffle tube. The result of these baffle systems is improved contrast in lunar, planetary, and deep space observing alike.

The mount's drive base is made of die-cast aluminum. The light-weight, but rigid, die-cast aluminum dual fork arms are shaped to damp vibrations quickly. There is a carrying handle on each fork arm. Both manual and electric slow motion controls are provided for both right ascension and declination. In addition to the digital readout of the scope's aiming point in right ascension and declination on the Autostar computer hand control, there are analog setting circles on the mount (5" in declination and 8.75" in right ascension). The drive base has a 4-port control panel, including two RS-232 serial interface ports for communication with an external computer and other ancillary equipment, such as the #909 Accessory Port Module.

The mount includes servo-controlled 12VDC slewing and tracking motors with 4.9" worm gear drives in both altitude and azimuth. The drive system has individually selectable drive speeds in both right ascension and declination - 6.5°/sec, 3°/sec, and 1.5°/sec for slewing and centering; as well as 128x, 64x, 16x, 8x, and 2x the sidereal rate for centering and astrophotographic guiding. In addition, there are standard lunar and sidereal tracking rates, plus a user-defined drive rate for precision tracking of the Sun and planets.

The scope is powered by eight user-supplied C-cell batteries that store in the drive base so you can use the LX90 in the field or your backyard without the need for a separate battery pack or AC power supply. The usable life of the batteries is up to 60 hours, depending on the ambient temperature (colder temperatures reduce usable battery life). An optional #541 adapter (with 25' cords) is available to allow you to power the scope from 110-120volt 60Hz AC household current in your backyard to conserve battery life, or to power the scope from your car's cigarette lighter plug or a rechargeable battery for extended use in the field.

The tripod (the same as the one used on Meade's premium 8" and 10" LX200GPS telescopes) adjusts in height from 30" to 44". It has 2" diameter steel legs that damp vibrations quickly, with a center leg brace that locks the legs firmly in place for added rigidity. Three 1.25" diameter holes in the leg brace can hold eyepieces while observing. A single threaded rod with a large hand-tighten knob simultaneously holds the scope firmly on the tripod and locks the legs rigidly in the most stable position.

The patented LNT (Level North Technology) of the LX-90 includes an electronic level sensor, an electronic magnetic North sensor, and a high precision internal clock. These components combine with the Level North Technology software in the built-in Autostar computer to make aligning on the sky as easy as remembering your own zip code. Simply take the scope outside and set it up on its supplied tripod. Tell the scope your location - either your latitude and longitude or your zip code. The scope will use its built-in level and magnetic North sensors to level the optical tube and point it north. The internal clock will tell the software the correct time. The software determines where and when on earth it is and what the sky looks like overhead. It then moves the scope automatically to its first alignment star.
    If the star is not precisely centered under the red dot in the SmartFinder non-magnifying finder, you can use the Autostar hand control pushbuttons to center it to improve the pointing accuracy. You can also use the supplied 8 x 50mm finderscope for even greater alignment accuracy. Let the scope repeat the process for its second alignment star and you're ready to start observing. The LNT system makes using the LX-90 almost as easy as using a GPS-equipped telescope, but for considerably less money.

The LX90's Autostar computer hand control plugs into the telescope's fork arm to permit a wide array of telescope options. First and foremost is its automatic go-to capability. The Autostar computer can show you the planets and thousands of deep space objects the very first night you use your scope - even if you've never used a telescope before! At the push of a button, the LX90 will move at a fast 6.5° per second to any of the 30,223 objects in its database. You can choose from 13,235 deep-sky objects from the complete Messier, Caldwell, IC, and NGC catalogs (sorted by name and type). Also included are 16,888 stars sorted by name, SAO catalog number, and by whether they are double or variable stars.
    The Autostar will also locate the centroids of all 88 constellations and 50 objects in the solar system (8 major planets from Mercury to Pluto; the Moon; 26 asteroids; and 15 periodic comets). You can use it to track 50 Earth satellites, including the International Space Station, the Hubble space telescope, and Mir, plus any of 200 user-defined objects. You can also automatically move to any object that's not in the database simply by entering its right ascension and declination coordinates. The Autostar moves the LX90 at any of nine user-selectable slewing and guiding speeds: 6.5°/sec, 3°/sec, and 1.5°/sec for slewing and centering; as well as 128x, 64x, 16x, 8x, and 2x the sidereal rate for centering and astrophotographic guiding. In addition, there are standard lunar and sidereal tracking rates, plus a user-defined drive rate for precision tracking of the Sun and planets. The Autostar includes a dual-axis Smart Drive drive corrector for long-exposure guided astrophotography. The Smart Drive has permanent periodic error correction that can be trained for finer and finer drive accuracy. You can even connect an optional #909 accessory port module to the rear cell of the LX90 to allow completely automatic CCD autoguiding of long exposure photos. The #909 also allows the use of an optional electric focuser and illuminated reticle eyepiece.
    The Autostar computer includes hundreds of special event menus, guided tours, a glossary, utility functions, and telescope status options. It also allows fast alignment of the telescope in either an equatorial or altazimuth mode using any of three alignment methods, including Meade's proprietary Easy Align method.
    The altazimuth drive of the LX90 is more than accurate enough for piggyback, lunar, and planetary 35mm photos and much CCD imaging. However, field rotation causes stars at the corners of an image to streak during exposures longer than five minutes if you don't use an equatorial wedge to align the scope on the celestial pole. So, if you plan on doing long exposure deep space photography, you'll need to add the optional #2590 LX90 equatorial wedge to your scope.

Optical features of this Telescope's Optical System . . .

• Advanced Coma-Free catadioptric designed to emulate the optical performance of a Ritchey-Chrétien telescope: The traditional two-mirror Ritchey-Chrétien (RC) telescope design uses approximately hyperbolic primary and secondary mirrors to produce images that are free from coma over a wide field. This wide coma-free field makes the Ritchey-Chrétien design particularly well suited to astrophotography. The traditional RC is the design of choice for most of the major professional observatory telescopes built in the last half-century. For example, the Hubble Space Telescope and the twin 10-meter Keck telescopes in Hawaii are Ritchey-Chrétiens.
  
      However, because of the complexity of fabricating and testing a large aperture hyperbolic mirror (just ask the people who built the initially-flawed Hubble Space Telescope), traditional two-mirror Ritchey-Chrétiens are very expensive to manufacture and purchase.
  
      To closely emulate the coma-free performance of traditional Ritchey-Chrétien optics, while keeping the cost of the telescope within reach and reason, Meade's Advanced Coma-Free catadioptric optical design uses a full aperture aspheric corrector lens in conjunction with a simple spherical primary mirror. This creates a two-element primary mirror/lens system that performs like a single hyperbolic mirror from the optical point of view of the secondary mirror. The secondary mirror itself is mounted directly on the rear of the corrector lens, rather than in the traditional RC's conventional spider vane assembly. This eliminates the image-degrading diffraction spikes of the secondary mirror support structure visible in traditional RC scopes. The result is Meade's Advanced Coma-Free catadioptric optical systems - RC-class coma-free wide-field performance, but at a cost far less than that of a pure RC reflector.
  
      The sophisticated corrector lens would be expensive to fabricate were it not for Meade's more than quarter-century of experience making Schmidt-Cassegrain correctors, which are in the same optical family as the corrector needed for the Advanced Coma-Free catadioptric design. An additional benefit of the full aperture corrector in the Advanced Coma-Free design is slightly better correction for astigmatism than a traditional RC scope.
  
      In addition, the MAX mount Advanced Coma-Free scopes, due to the front corrector plate, are essentially a closed tube design (however, due to the front cell focusing method discussed below, there is an small opening between the tube wall and the periphery of the corrector, which prevents the tube from being totally sealed). This essentially closed tube design reduces the amount of image-degrading dust, moisture and other contaminates that would otherwise fall on the optical surfaces of the primary and secondary mirrors as is the case with traditional open-tube RC designs. While a Meade Advanced Coma-Free telescope may not employ a traditional RC design, its performance is RC-like in all important characteristics.
      A review in Sky & Telescope magazine said a Meade Advanced Coma-Free optical system "does indeed perform like a Ritchey-Chrétien." A review in Astronomy magazine said, "This scope delivers Ritchey-Chrétien-like performance at a fraction of the cost."
  

• Fully multicoated UHTC (Ultra High Transmission Coatings) optics: The primary and secondary mirrors are vacuum-coated with aluminum, enhanced with multiple layers of titanium dioxide and silicon dioxide for increased reflectivity. A overcoating layer of silicon monoxide (quartz) assures long life.
      A series of anti-reflective coatings of aluminum oxide, titanium dioxide, and magnesium fluoride are vacuum-deposited on both sides of the full aperture corrector plate. These antireflection multicoatings provide a high 99.8% light transmission per surface, versus a per-surface transmission of 98.7% for standard single-layer coatings. Overall light throughput (the amount of light collected by the objective lens that actually reaches your eye or camera) is approximately 89% at the Cassegrain focus.
      UHTC multicoatings provide a 15% increase in light throughput compared with standard coatings. They effectively add the equivalent of 15% extra light-gathering area to the performance of a scope with standard coatings. It's the equivalent of three-quarters of an inch of extra aperture in the case of a 10" scope, for example, but with no increase in actual size or weight. UHTC coatings also improve contrast, for lunar and planetary images that appear sharper and more crisply defined.

Mechanical features of this Telescope's Optical System . . .

• Fixed primary mirror with computer optimized primary and secondary baffling: Unlike traditional catadioptric designs (Schmidt-Cassegrains and Maksutov-Cassegrains) that move the primary mirror fore and aft along the central baffle tube in order to achieve focus, the ACF system's primary mirror is fixed and independent of the baffle tube. The primary mirror is laser aligned to the true optical path, then float-bonded in place on the rear cell. Although fixed in position in the optical tube, it literally floats on a layer of adhesive instead of resting on the baffle tube. This results in zero stress to the glass and no distortion in the optics (unlike conventional mirror cells, which can cause pinched optics if not properly assembled). This fixed and independent mirror allows a no-compromise baffle design with full stray light cut-off, producing the maximum possible contrast. A series of field stops machined into the inner surface of the baffle tube effectively eliminates undesirable light which might reflect from the inside surface of the tube.
      The secondary mirror baffle, which is attached directly to the rear of the full aperture corrector plate, is machined of aluminum with a series of distinctive knife-edges around its outside. These prevent stray off-axis light from reaching the image plane. The result of these primary and secondary baffle systems is improved contrast in lunar, planetary, and deep space observing alike.

• Encoder-measured digital front cell focusing: The patented Meade electric front focusing system produces a razor sharp focus, with no image shift. With the laser-aligned primary mirror fixed in position, focusing is done by using three encoder-controlled motors to precisely move the entire corrector lens, with its attached secondary mirror, fore and aft in the front cell. It moves in increments as fine as 1/100 of a millimeter, at any of four different focusing speeds. There's a digital readout of the focus position on the telescope's computer hand control. Since focusing is accomplished without sliding the primary mirror along the baffle tube, image shift (once the bane of CCD astrophotographers because it could easily move the image off a small CCD chip) is virtually non-existent.

• Electronic focus presets: The electric focuser allows the observer to preset up to nine individual focus positions to customize the focus for observers with differing eyesight characteristics (similar to the custom settings in luxury cars that change the mirror, seat, and steering wheel settings from one driver to another). The feature is also very useful when switching between various eyepiece and Barlow combinations, or when switching from a visual setup to a camera setup.

• Electronic collimation: Precision collimation adjustments to the secondary mirror are made electronically by using the arrow keys of the computer hand control while observing, rather than by using a screwdriver or hex-head wrench to adjust small collimating screws in the dark on a trial and error basis. The observer sees the results of a collimating adjustment instantly as it is made, shortening the time needed to collimate the scope by as much as a factor of ten. Collimating a Cassegrain telescope has never been easier.
      In addition, Meade precisely collimates the optics at the factory and sets that position as the default setting in the scope's computer. So, if a newcomer to astronomy succeeds in accidentally decollimating the scope, rather than having to recollimate it, he or she can always return to the correct factory default setting by simply pushing a button.

• Built-in dew heater: Aftermarket dew heaters wrap a heating element around the telescope's optical tube to send heat through the scope's metal front cell to warm the corrector. This prevents dew from forming on the corrector plate. Having to heat the entire metal cell in order to slightly warm the lens can drain a battery quickly. The large aperture ACF systems incorporate a standard equipment nickel-chromium wire heating element that is in direct contact with the glass of the corrector plate. This quickly, efficiently, and safely warms the lens using the lowest power drain possible.
      There are two onboard temperature sensors, one inside the fork arm to measure the ambient temperature, and one to measure the temperature of the corrector plate itself. By using the information from these two sensors, the built-in dew heater can be set to keep the corrector plate warmed to a user-defined setting just above ambient temperature. By automatically using the dew heater only when needed, battery drain is kept to a minimum. All functions to operate the dew heater are controlled by the computer hand control.

• Advanced front and rear cell architecture: The front and rear cells of the large aperture ACF systems are designed to allow the maximum amount of air-flow around the optics to achieve the quickest "cool down" times. To accelerate the cool-down, a built-in fan on the rear cell can be turned on and off through the computer hand control.
      The rear cell incorporates a panel with eight electronic ports - three USB 2.0 ports to connect auxiliary equipment, an autoguider input, the input for the computer hand control, an output to power an illuminated reticle eyepiece, an RS232 communications port, and a port for future "smart" accessories. Some equipment moves with the scope, such as the computer hand control and an optional CCD camera. Attaching the cords and cables of this equipment directly to the tube, rather than stretching them to attach to the drive base, virtually eliminates cord wrap. This protects CCD cameras and other accessories from accidentally pulling out of the telescope as the scope slews. The rear cell is flatter than conventional scopes to maximize the clearance between the rear cell and the fork mount. Two tube positioning handles are built into the rear cell.

• Carbon fiber and Kevlar optical tube: The optical tube is fabricated from a woven carbon fiber and Kevlar composite that forms a unique, light-weight, and high strength material. It has ultra-low thermal expansion characteristics. This maintains the critical spacing between the optics so that the focus does not change due to tube expansion and contraction as the ambient temperature changes, a critical feature to astrophotographers.
      Instead of forcing the mechanics of the scope to fit into a perfectly round optical tube assembly, the tube is shaped to conform to the internal mechanisms and drive system of the front focus and collimation assembly. This "form follows function" philosophy gives a large aperture ACF optical tube its unique look and style.

This Telescope's Autostar II Computer, Smart Mount, and GPS System . . .

• GPS/Autostar II computer operation: The operation of an RCX400 is simplicity itself. Once you mount the scope on its heavy-duty tripod, simply turn it on. An integrated true-level electronic sensor levels the optical tube parallel to the ground. A 16-channel Sony GPS (global positioning satellite) receiver in the left fork arm uses a network of earth-orbiting government satellites to quickly triangulate the scope's position on the earth with an accuracy measured in meters and then determine the local time to fraction of a second accuracy. A built-in electronic compass automatically rotates the scope optical tube to aim it due north (the home position). This is a tremendous help if trees or buildings block your view of the north. Built-in software compensates for magnetic declination errors (the difference between true north and magnetic north at your observing location).
      Once the scope reaches the home position (it only takes a minute or two), press the "enter" button on the Autostar II hand controller to start the astronomical alignment. The RCX400 slews at 8° per second to the first of two alignment stars. If that star is not centered in the eyepiece, a touch or two on the Autostar II hand control directional push buttons quickly centers it. Do the same with the second alignment star the scope moves to and you're ready to observe or image. For the rest of the evening, a computer in the Autostar II controls the scope's altitude and azimuth motors to keep you precisely centered on whatever you aim at, for as long as you want to observe.
      It takes only a few moments to begin observing, since you never have to line up on the celestial pole, take the time to precisely level the tripod, input observing latitude and longitude and accurate local time, or adjust imprecise manual setting circles to match the sky.

• Autostar II computer: This scope's Autostar II computer can show you the planets and thousands of deep space objects the very first night you use your scope - even if you've never used a telescope before! The computer's expanded 4 megabyte flash memory (which you can upgrade at any time for free via the internet) contains the following objects:
  
  • the entire NGC (New General Catalog) of 7840 nebulas, galaxies, and star clusters
    
  • the IC (Index Catalog) of 5386 nebulas, galaxies, and star clusters
    
  • the Messier Catalog of the 110 best known deep sky objects
    
  • the Caldwell Catalog of 109 fascinating objects that Messier missed
    
  • 227 named objects
    
  • the Herschel Catalog of 400 faint and difficult deep sky objects
    
  • the Abell Catalog of 2712 galaxy clusters
    
  • the Arp Catalog of 645 irregular galaxies
    
  • the Uppsala Galaxy Catalog of 12,940 galaxies
    
  • a portion of the Russian Morphological Catalog listing 12,939 of its 30,642 galaxies down to magnitude 15
    
  • the Sharpless Catalog of HII Regions
    
  • the General Catalog of 28,484 variable stars
    
  • the SAO and Hipparcos/Tycho Star Catalogs of more than 31,000 stars
    
  • a subset of the finest visual double stars from the Wisconsin Double Star Catalog
    
  • the Hickson Catalog of Dense Galaxy Groups
    
  • the Gleason Catalog of Nearby Stars
    
  • the Landolt Catalog of Photometric Standard Stars
    
  • the General Catalog of 28,484 variable stars
    
  • the "Lunar 100" list of the finest features to see and image on the Moon
    
  • SAO and Hipparcos Star Catalogs of 31,090 stars
    
  • Also included are the eight major planets out to Pluto, the Moon, asteroids, meteor showers and their radiants, comets, Earth satellites, and more.
    
  • You can also add your own selected favorite deep sky objects in a separate catalog. The Autostar II computer keeps a total database of more than 180,000 stars and objects in its memory for you to observe.
  
      Granted, a good number of the faintest objects will not be visible in an eyepiece in the smaller aperture telescopes (for example, the 15th magnitude galaxies of the Russian Morphological Catalog are not eyepiece objects in a 10" scope that has a visual limiting magnitude of 14.5 under perfect dark sky seeing conditions), but they are all photographable with any RCX400 given the right equipment and a modicum of persistence.
      Simply call up any of these 180,000+ discrete objects on the Autostar II hand control's two line/sixteen character night-vision red screen by using the 20-button numeric keypad. Then press the "go-to" key. The RCX400 slews to that object at a fast 8° per second (barely 11 seconds to go from horizon to zenith). The telescope quickly centers your chosen object in the field of view for you to enjoy. It routinely centers objects with an accuracy that puts them well within the field of the standard equipment 2" 24mm Series 5000 Ultra Wide Angle eyepiece (usually within two arc minutes of dead center). The supplied Smart Mount Technology system (see below) can improve that accuracy still further.
      Once the object is located, the hand control screen tells you its catalog number, type, magnitude, size, right ascension, and declination. If you have the coordinates of an object not in the computer's memory (a comet or asteroid, for example), enter those coordinates, press "go-to," and your RCX400 takes you there, as well. You can find faint deep space objects almost faster than you can read about it. If you want to scan the skies on your own, the Autostar II keypad lets you move the scope in any direction at any of nine scanning and centering speeds up to 8° per second.
      The RCX400 Autostar II computer includes an RS232 serial port for interfacing with a Windows-equipped computer. This allows remote control of the scope, as well as the ability to upgrade the operating system and database at any time at no cost through Meade's website. In addition, current Earth satellite orbital data (including the International Space Station, Space Shuttle, etc.) may be downloaded. The telescope then automatically locates and tracks the satellite at the correct tracking rate.
      The scope hand control provides brightness control of the computer keypad, a real-time digital readout of the telescope position in right ascension and declination, and a variety of other unique keypad/display panel functions.

• Smart Drive: The RCX400 has built-in dual-axis Smart Drive permanent periodic error correction (PPEC) to make deep space photography easier. This computer circuit automatically corrects for the minor drive errors present in every telescope - regardless of size, brand, or cost. All worm/worm-gear combinations, no matter how well made, have minor inaccuracies that manifest themselves as periodic errors in the telescope tracking rate, with the period dependent on the worm's rate of rotation. PPEC reduces by up to 90% the number of guiding corrections needed to compensate for these errors during long exposure photos. Simply use an optional illuminated reticle eyepiece to guide once on a star for a short time. Use the Autostar II hand control to make the corrections needed to keep the star centered on the eyepiece crosshairs. The Smart Drive remembers those corrections and automatically plays them back whenever the telescope is operating - virtually eliminating repetitive corrections during astrophotography.
      The dual-axis Smart Drive even corrects for declination errors, not just right ascension errors as with competitive scopes. Smart Drive software can achieve periodic errors of 5 arc seconds or less - an observatory standard of precision. In CCD imaging, where short exposures of deep-space objects are often all that is required for stunning results, the Smart Drive often permits imaging without any manual guiding at all.

• Smart Mount Technology (SMT): This standard equipment software program provides improved (and constantly improvable) pointing accuracy with an RCX400. The already high pointing accuracy of the telescope is further refined with every object that you center precisely and synchronize on during a night's observing. The program works in both altazimuth and equatorial modes. It includes a simple routine to refine the pointing accuracy for the entire sky with your particular equipment configuration and alignment. The refined pointing data can be saved and reused for both permanent and portable setups.

• High Precision (HP) pointing capability: The RCX400 permits the most accurate pointing capability ever offered in a commercial telescope. You can command the telescope to go to an object located on the opposite side of the sky (for example, a distance of 120 degrees in sky-angle) and, in conjunction with the telescope's unique sync command, the RCX400 precisely locates and centers the desired object. HP capability is accessible in either the altazimuth or equatorial mode of operation.

    The mount's drive base is made of heavy-duty die-cast aluminum, as are the dual fork arms that support the optical tube. The U-shaped base of the fork arm assembly is cast as a single unit to provide the strongest, most rigid optical tube mounting ever available for a telescope of this aperture. The fork arms themselves are shaped to damp vibrations quickly and do the job very well. There are dual carrying handles on each fork arm, as well as dual positioning handles on the rear of the optical tube itself. An adjustable angle holder is supplied for hands-free use of the Autostar II computer. This can be mounted on either the right or left fork arm, to accommodate either right-handed and left-handed observers.

    The complete optical tube, fork arm, and drive base assembly is quite heavy. It will be difficult for one person to lift up a 10" scope and assemble it on the tripod in the field on their own, very difficult with a 12" scope, almost impossible with a 14" scope, and forget about it with a 16". We recommend an able-bodied assistant to help assemble the scope in all cases, particularly the 12" and larger.

    Manual and electric slow motion controls are provided in both right ascension and declination. There are analog setting circles on the mount, in addition to the digital r. a. and dec readouts on the AutoStar II computer hand control.

    The drive base has a 7-port multi-function control panel that includes a special single USB port to allow simultaneous control over the telescope and either the Meade Lunar Planetary Imager or Deep Sky Imager camera through Meade's AutoStar Suite software. Additionally there is a power cord input and ports for the AutoStar II hand control, a DB-9 auxiliary port, a 12VDC power output port, and an RS-232 communications port. The drive base also includes the familiar on/off switch and an LED power light indicator.

    The mount includes servo-controlled 12VDC slewing and tracking motors with 5.75" worm gear drives in both altitude and azimuth. The RCX Balanced Drive worm block design is used on both the right ascension and declination axes. This drive assembly, first used and proven on the 14" LX200GPS, incorporates a unique balanced loading system that keeps the worm and drive gear in the optimum contact position, regardless of the load stress that is normally encountered as the telescope is moved from one area of the sky to another. The result is improved drive performance, with superior centering and slewing characteristics.

    The drive system has almost 200 individually selectable drive speeds in both right ascension and declination to permit observatory-level precision in tracking, guiding, and slewing. Photoguide speeds are selectable from 0.01x to 1.0x sidereal, in increments of 0.01x. Fast-slew speeds are selectable from 1°/second to 8°/second in 0.1°/second increments. You can use the 8°/second speed for rapid motion of the telescope across the skies. Once near the target, you can switch instantly to a speed of 1.5° or 3°/second for centering in the viewfinder. Observing through the main telescope, you can use the 16x or 64x sidereal speed to place the object in the center of the field. You can select either a sidereal or lunar tracking rate, or you can custom-select a drive speed from 2000 incremental rates to match solar or planetary motions.

    The scope is powered by eight user-supplied C-cell batteries that fit into the fork arms. You don't need an external battery pack or AC power supply as you do with competitive scopes. Battery life is typically about 20 hours in warm weather, decreasing as the amount of slewing increases or as the temperature drops. Optional adapters (with 25' cords) are available to allow you to power the scope from 110-120 volt 60 Hz AC household current in your back yard to conserve battery life, or to power the scope from your car's cigarette lighter plug or a rechargeable battery for extended use in the field.