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This Telescope’s Optical System . . .

• Schmidt-Cassegrain optical tube: 8” aperture (2000mm focal length f/10), guaranteed to be diffraction-limited. The primary and secondary mirrors are crafted of low thermal expansion Pyrex optical glass. The Schmidt corrector lens is made of water white glass, for up to 10% higher light transmission than conventional soda-lime (plate) glass. The seemingly-flat Schmidt corrector has a subtle aspheric curve ground into it that compensates for the primary mirror’s spherical aberration for tighter star images over a wide field. The primary mirror is 8.25” in diameter, 3% larger in diameter (6% larger in area) than the 8” aperture of the Schmidt corrector lens. This gives you a wider fully-illuminated field than a conventional 8” SCT – with about 6% more off-axis light available to your eye or camera. The optics, made entirely at Meade’s Irvine, CA, optical shop, are mounted in machined aluminum cells that are fitted to a white-enameled steel tube.

• UHTC multicoated optics: The primary and secondary mirrors are coated with a complex multi-layer stack of aluminum enhanced with titanium dioxide and silicon dioxide. This increases the reflectivity of each mirror to 97% instead of the 89% of standard aluminum coatings. In addition, the silicon dioxide (quartz) layer assures a long coating life. Antireflection coatings consisting of multiple layers of aluminum oxide, titanium dioxide, and magnesium fluoride are applied to both sides of the Schmidt corrector lens for higher light transmission. Per-surface light transmission of the corrector is 99.8%, versus a per-surface transmission of 98.7% for standard magnesium fluoride coatings.
      These coatings effectively add the equivalent of over three-quarters of an inch of light-gathering aperture to the scope, with no increase in the size or weight of the scope. This gives visibly brighter deep space images in a side-by-side comparison with standard optics of the same size.

• Fully-baffled optics: A series of glare stops machined into the inner surface of the central baffle tube of the scope prevents stray off-axis light from reaching the image plane. This yields a contrast improvement for lunar, planetary, and deep space observing alike.

• Finderscope: 8 x 50mm straight-through achromatic design in a quick-release dual ring bracket. The finder has a wide 5.8° field of view that makes it easy to locate objects. Focuses by loosening the trim ring behind the objective lens cell, screwing the lens cell in or out to focus, and tightening the trim ring to lock in the correct focus.

• Star diagonal: 1.25” prism type.

• Eyepiece: 1.25” 26mm Super Plössl eyepiece (77x) with a 0.65° field of view (30% wider than the full Moon) for sharp images of the lunar landscape, star clusters, and the brighter nebulas and galaxies. Higher-power lunar and planetary images, using optional eyepieces and/or Barlows, reveal subtle details that are often lost in telescopes of lesser optical resolution. Optional lower power eyepieces can give bright images encompassing volumes of space three lunar diameters across.

This Telescope’s Mount . . .

• Heavy duty LXD75 computerized German equatorial mount: The white-painted mount is machined of aluminum for durability and high-performance photo/visual observing. Four high-precision stainless steel ball bearings support the right ascension and declination axes for smooth motion in all directions. The mount has high-precision worm gear drives and electric slow motion controls in both right ascension and declination. Enhanced precision alignment of the motor gear assembly assures greatly reduced backlash and tracking smoothness. The dual-axis slewing/tracking motors have nine user-selectable slew and slow-motion speeds: 4.5°, 3°, and 1.5° per second; and 128x, 64x, 16x, 8x, 2x, and 1x the sidereal rate. Automatic sidereal-rate tracking in right ascension keeps objects precisely centered in the field for leisurely observing. Power for the dual-axis drives is supplied by a battery pack that rests on the telescope’s accessory shelf and plugs into the control panel. The pack uses eight (user-supplied) D-cell batteries that will power the scope for as long as 40 hours, depending on the temperature (low temperatures will reduce the usable battery life). Optional adapters with 25’ cords are available for uninterrupted AC and 12 volt DC car battery operation, as well.
      If serious long exposure astrophotography is in your plans, a supplied illuminated polar viewfinder and micrometric altitude and azimuth controls allow quick, precise polar alignment. A periodic error correction circuit in the computer control lets you train the mount to correct the small right ascension drive errors inherent in all telescope drive systems. This minimizes the number of guiding corrections needed during long exposure astrophotography. A high precision pointing subroutine in the computer lets you point accurately at objects that you want to photograph that are too dim to be seen though the scope.
      The mount’s sliding counterweight is locked in place with a single hand-tighten lever , making it easy to rebalance the scope if you add heavy photographic accessories. The mount is easily capable of handling the scope and any reasonable combination of photographic accessories you might want to use. although an additional optional counterweight may be needed if you add a significant amount of weight (such as a photoguide scope and mounting rings in addition to a camera). Snap-on covers keep the motor drives and polar alignment scope free from dust and debris.

• AutoStar computer hand control: The built-in Autostar dual-axis electronic control system has a database of 30,223 objects it can find and track for you. They are accessed using a 20-key alphanumeric keypad hand control on a 24” coiled cord. There are 13,235 non-stellar deep sky objects, including the complete Messier, Caldwell, IC, and NGC catalogs, although not all objects are visible in this size scope. There are also 16,888 stars sorted by name, SAO catalog number, and whether they are double or variable stars. You also get the 8 major planets; the Moon; 26 asteroids; 15 comets, and 50 Earth satellites. In addition, there are 200 memory locations available for storing your own user-defined objects, such as the coordinates of asteroids and new comets that are printed regularly in Astronomy and Sky & Telescope magazines. In addition to the 30,223 objects in its database, the Autostar can automatically move the scope to any object with known right ascension and declination coordinates.
      The Autostar hand control gives you a digital readout of r. a. and dec coordinates; scrolling information about the object being viewed; plus the results of calculations about sunrise, sunset, moonrise, moonset, moon phases, solar eclipses, lunar eclipses, the minimum of Algol, and more. Hypertext links on the Autostar screen display define many of the terms used in the computer (there's more than one megabyte of compressed text stored in the Autostar.) Built-in guided tours of the sky are tailored to the day of the year you are observing. They direct you to showpiece objects, including the Moon and any planets then visible. Most of the tour objects are accompanied by descriptions scrolling across the Autostar display (the description of Algol, for example, is over 300 words long). The Moon has different descriptions based on its phase, and prominent features near the terminator are highlighted.
      All of the database and scope operation information is displayed on a two line, 16-character, LED display on the hand control. A numeric keypad on the hand control gives complete control over the many, many Autostar functions and convenience features. On-screen operation instructions guide you through setup and use of the Autostar and a help function is only a keystroke away. You can control the telescope with your laptop or PC and upgrade its software over the Internet, using the built-in RS-232 serial interface and the standard equipment Autostar Software Suite described below.
      The computer uses a three-star alignment method to precisely align the scope’s optical and mechanical systems on the heavens. Alignment is easily accomplished in only a few short minutes. You can be observing in less than 15 minutes after you first take the scope outdoors.

• Adjustable height tripod: The tripod has tubular chromed steel legs. Each leg has two anodized aluminum leg extension locks with an internal brake to eliminate accidental slippage of the internal extending leg section. These locks face inwards to prevent snagging your clothing or gouging your shin as often happens when running into outward-facing leg locks in the dark. A center leg brace adds rigidity and excellent damping characteristics. A set of optional #895 vibration suppression pads under the tripod feet will even further improve telescope damping time for steadier high power observing. The center leg brace is drilled to form a convenient accessory tray that holds three 1.25” eyepieces to keep them up out of the dew-soaked grass.

• Dovetail slide bar: An adjustable dovetail slide bar allows the optical tube to be quickly and precisely balanced fore and aft on the mount, eliminating the need for an extra counterweight to balance a camera or other accessories. Setup and takedown times are exceptionally fast, as a single large hand-tighten knob holds the optical tube in place. A second lock knob prevents the tube from sliding off the mount should the hand-tighten knob loosen.

What can you see through this scope:

    Given the right assortment of eyepieces, you can see virtually all the Universe! Under good seeing conditions, no less than six of Saturn’s moons can be seen shuttling around the visibly multi-ringed planet. Distant galaxies barely visible in other telescopes begin to show their essential structure. The UHTC multicoatings show nebular wisps and fragments with markedly wider extent than any identical aperture scope with standard coatings. Orion’s nebulosity often fills your entire field of view, particularly with a narrow band light pollution filter to increase the contrast of the fainter segments. Densely packed globular clusters are often resolved to the core. Even cold and distant Pluto, a faint magnitude 13.8 speck, can occasionally be glimpsed making its lonely way across the skies under appropriate seeing conditions.
    While this 8” scope performs well under mildly light-polluted suburban skies, it is at a remote site with truly dark and steady skies that you’ll best be able to take full advantage of its superb optical performance. It’s not a scope that’s happy staying in a heavily light-polluted city or suburban observing environment. Luckily (actually more by design than by luck) the 8” LXD75 is a scope that one person can easily move to a dark sky site and set up by himself or herself. Since the self-contained scope runs off flashlight batteries, there’s no need to haul power adapters or a portable power supply with you, making transport and setup easier still. This 8” scope and its enhanced optics can keep you busy observing and photographing for the rest of your life . . . at a price that won’t break the bank.