Meade's LX200-ACF brings Advanced Coma-Free (ACF) optics within reach of aspiring astronomers everywhere. Nearly every observatory reflector in the world uses an aplanatic (coma-free) optical system like the Ritchey-Chrétien (RC), including NASA's Hubble Space Telescope. Now you can own similar optics to what the professionals use. The LX200-ACF includes all the field-proven features of the LX200 including GPS, Primary Mirror Lock, Oversized Primary Mirror, SmartDrive™, Smart Mount™, AutoStar® II and more. The new LX200-ACF. It's the biggest news in astronomy since, well, the LX200.
- Advanced Coma-Free ACF Optics
- Meade Ultra-High Transmission Coatings UHTC
- Zero Image Focuser
- Oversized Primary Mirror
- Primary Mirror Lock
- Smart Drive GPS Receiver
- Auto Align
- Auto Star
f/10 Advanced Coma-Free (ACF) Optics. Building from a classic RC design, Meade has created a new design with the same coma-free pinpoint star images and flatter field also reduces the astigmatism and eliminates diffractions spikes found in classical RCs. The LX200-ACF is the perfect platform for the demanding researcher and imaging enthusiast with telescopes available in apertures of 8 inches, 10 inches, 12 inches, 14 inches, and 16 inches. However, let's get to step one first and disect why ACF technology is so beneficial and how it functions. Using the fundamentals behind the Ritchey Chretien design, ACF just adds even more to the big picture. Diffraction refers to various phenomena which occur when a wave encounters an obstacle. Coma is very similar to diffraction effects, in which light from a specific object cannot be focused properly and therefore results in fuzzy. undetiled, and inaccurate images. Since this is purely an optical aberration and widely understood, there is absolutely NO reason why it cannot be fixed to near perfection. With this new technology by Meade directly built into the optics, observors can now obtain a more aplanatic (coma-free) and spherical free telescopic experience. Years ago, this luxury would've costed a minimum of a few thousand dollars, but with Meade's invention, that is pure HISTORY!
Meade Ultra-High Transmission Coatings (UHTC™). Increasing total light transmission and image brightness by nearly 20% over Meade's standard coatings. Objects such as stars, galaxies and nebulae will appear significantly brighter. More details are below.
An important optional feature to optimize the performance of your Meade telescope.
Image brightness in a telescope is crucially dependent on the reflectivity of the telescope's mirrors and on the transmission of its lenses. Neither of these processes, mirror-reflectivity or lens-transmission, is, however, perfect; light loss occurs in each instance where light is reflected or transmitted. Uncoated glass, for example, reflects about 4% of the light impacting it; in the case of an uncoated lens 4% of the light is lost at entrance to and at exit from the lens, for a total light loss of about 8%.
Early reflecting telescopes of the 1700's and 1800's suffered greatly from mirrors of poor reflectivity — reflection losses of 50% or more were not uncommon. Later, silvered mirrors improved reflectivity, but at high cost and with poor durability. Modern optical coatings have succeeded in reducing mirror-reflection and lens-transmission losses to acceptable levels at reasonable cost.
Meade Standard Coatings: The optical surfaces of all Meade telescopes include high-grade optical coatings fully consistent in quality with the precision of the optical surfaces themselves. These standard-equipment coatings include mirror surfaces of highly purified aluminum, vacuum-deposited at high temperature and overcoated with silicon monoxide (SiO), and correcting lenses coated on both sides for high light transmission with magnesium fluoride (MgF2). Meade standard mirror and lens coatings equal or exceed the reflectivity and transmission, respectively, of virtually any optical coatings currently offered in the commercial telescope industry.
The Meade UHTC Group: Technologies recently developed at the Meade Irvine coatings facility, however, including installation of some of the largest and most advanced vacuum coating instrumentation currently available, have permitted the vacuum-deposition of a series of exotic optical coatings precisely tuned to optimize the visual, photographic, and CCD imaging performance of Meade telescopes. These specialized, and extremely advantageous, coatings are offered here as the Meade Ultra-High Transmission Coatings (UHTC) group, a coatings group available optionally on many Meade telescope models. In Meade catadioptric, or mirror-lens, telescopes (including the ETX-90AT, ETX-105AT, and ETX-125AT; LX10, LX90, and LX200GPS Schmidt-Cassegrains; and LXD55-Series Schmidt-Newtonians) before incoming light is brought to a focus, it passes through, or is reflected by, four optical surfaces: the front surface of the correcting lens, the rear surface of the correcting lens, the primary mirror, and the secondary mirror. Each of these four surfaces results in some loss of light, with the level of loss being dependent on the chemistry of each surface's optical coatings and on the wavelength of light. (Standard aluminum mirror coatings, for example, typically have their highest reflectivity in the yellow region of the visual spectrum, at a wavelength of about 580nm.) Mirror Coatings: Meade ETX, Schmidt-Cassegrain, and Schmidt-Newtonian telescopes equipped with the Ultra-High Transmission Coatings group include primary and secondary mirrors coated with aluminum enhanced with a complex stack of multi-layer coatings of titanium dioxide (TiO2) and silicon dioxide (SiO2). The thickness of each coating layer is precisely controlled to within 1% of optimal thickness. The result is a dramatic increase in mirror reflectivity across the entire visible spectrum.
Correcting Lens Coatings: Meade telescopes ordered with the UHTC group include, in addition, an exotic and tightly-controlled series of coatings on both sides of the correcting lens or correcting plate, coatings which include multiple layers of aluminum oxide (Al2O3), titanium dioxide (TiO2), and magnesium fluoride (MgF2). Per-surface light transmission of the correcting lens is thereby increased at the yellow wavelength of 580nm., for example, to 99.8%, versus a per-surface transmission of 98.7% for the standard coating.
The importance of the UHTC group becomes apparent when comparing total telescope light transmission, or throughput, caused by the multiplier, or compounding, effect of the four optical surfaces. With each optical surface contributing significantly to telescope light throughput, the effect of all four surfaces combined is indeed dramatic, as demonstrated by the graphs on the facing page, as well as by the table of the brightest nebular emission lines. At the H-a wavelength of 656nm., total transmission increases from 76.7% to 88.5%, an increase of 15.4%; at the helium wavelengths of 588nm. and 469nm. — strong emission lines in hot planetary nebulae — total telescope transmission increases by 13.8% and 16.8%, respectively; at the two nitrogen II lines of 655nm. and 658nm. and at the sulfur II line of 673nm., transmission is increased by 16%. Averaged over the entire visible spectrum (450nm. to 700nm.), total light transmission to the telescope focus increases by about 15%.
An important optional feature to optimize the performance of your Meade telescope. Image brightness in a telescope is crucially dependent on the reflectivity of the telescope's mirrors and on the transmission of its lenses. Neither of these processes, mirror-reflectivity or lens-transmission, is, however, perfect; light loss occurs in each instance where light is reflected or transmitted. Uncoated glass, for example, reflects about 4% of the light impacting it; in the case of an uncoated lens 4% of the light is lost at entrance to and at exit from the lens, for a total light loss of about 8%. Early reflecting telescopes of the 1700's and 1800's suffered greatly from mirrors of poor reflectivity — reflection losses of 50% or more were not uncommon. Later, silvered mirrors improved reflectivity, but at high cost and with poor durability. Modern optical coatings have succeeded in reducing mirror-reflection and lens-transmission losses to acceptable levels at reasonable cost.
Zero Image-Shift Microfocuser. Optional for the 8", 10", 12",14" and standard with the 16" models, allows you to obtain precise image focus with no image movement. Perfect for astroimaging or during planetary observation. Focus is controlled thru the Autostar II handbox. The Meade #1209 Zero Image-Shift Microfocuser allows precise, vibration-free image focus during visual, CCD, and astrophotographic applications. It also allows you to achieve focus without causing a viewed object to move out of position in the eyepiece. The microfocuser comes equipped with a handbox which requires 8 AAA batteries (user-supplied). The microfocuser maintains precise image centering on even the smallest CCD chips. The microfocuser operates at four speeds.
Oversized Primary Mirror. Meade primary mirror diameters are greater than their listed aperture (e.g., the diameter of the 8" LX200-ACF is actually 8.25"). This additional 1/4" yields a wide, fully illuminated field-of-view.
Smart Drive™ provides permanent periodic error correction (PPEC) on both axes by learning and averaging error over the course of one or more training periods, thereby minimizing guiding corrections during long-exposure photographs. PPEC is available on both axes and functions in both polar and altazimuth modes.
GPS Receiver automatically inputs precise time, date, and geographical location to help quickly and precisely align the telescope. Communicating with satellites provides relief of stress and extra time to align the telescope correctly. This GPS Reciever along with the mirror lock decreases the overall chance of the telescope becoming misaligned due to bumping or other minor movement.
AutoAlign™. Telescopes with Meade's AutoAlign are smart scopes that know the night sky right out of the box. AutoAlign picks two alignment stars for you and places them right in your view-finder. Just center to fine tune your alignment and the wonders of the universe are at your fingertips. This feature will also provide a reasonable indication to how precise and accurate the telescope is aligned right out of the box before you begin to use it. So if AutoAlign manages to perfectly center image the star without any human intervention, chances are you as the observor are already ready to observe!
AutoStar® II controller features "Hot Keys" for quick access to a 145,000 celestial object database. AutoStar II can be updated with the latest software upgrades, guided tours and timely objects like comets free at meade.com.
Back to top
|Name||Meade - LX200R 8 " Advanced Ritchey-Cretien Optical Tube Only with UHTC - Refurbished|
|Custom Stock Status||Ships in 3-5 Days|
|Mount||Dual fork GPS equipped mount with GOTO|
|Optical Design||Advanced Coma-Free (ACF) with UHTC|