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Meade - ETX-125PE with UHTC - ASTRO TUBE with 3 Year Sky Assurance
SUPER SPECIAL BLOWOUT PROMOTION!!! (while supplies lasts)
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$ 790.99
$ 1098.00
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| 0515-03-31_SKY
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Click here for recommended accessories |
SUPER SPECIAL BLOWOUT PROMOTION!!! (while supplies lasts) |
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EasyAlign with SmartFinder
Meade’s new ETX-Premier Edition automatically levels your telescope, points it North and sets the
time. You just enter your location or zip code. After your ETX completes its patented Level North
automatic alignment procedure it will point to the first alignment star. Use the new wide-field
SmartFinder to center the red dot over the alignment stars for ultra-precise pointing accuracy,
It’s that easy.
* Electronic Level Sensor
* Electronic Magnetic North Sensor
* High Precision Clock
* Red Dot ViewfinderThis Telescope’s Optical System . . .
* Maksutov-Cassegrain fully-coated optics: 125mm (5.0”) aperture, 1900mm focal length,
f/15 focal ratio. Guaranteed diffraction-limited optical performance. The meniscus corrector lens
is Grade-A BK7 optical glass. The primary mirror is low-expansion Pyrex. There are standard
aluminum coatings on the primary mirror and on the secondary mirror spot on the rear of the
meniscus corrector. Both aluminized surfaces are overcoated with silicon monoxide (quartz) for
long life. Magnesium fluoride antireflection coatings on both sides of the corrector lens provide
high light transmission.
* Multicoated optics available as an option: For images that are up to 20% brighter,
Meade offers the ETX-125PE with optional UHTC(Ultra High Transmission Coatings) optics. These
multicoated optics add the equivalent of a third of an inch of additional aperture to the scope’s
light grasp, for brighter deep space images than a scope with standard coatings.
* Dust covers: A thread-in metal dust cover protects the meniscus lens. A thread-on
metal cap seals the Cassegrain focus on the rear cell.
* Finderscope: A straight-through wide-field red dot SmartFinder allows easy
non-magnified views of the sky, with a projected red dot of light showing exactly where the scope
is pointed at all times.
* Star diagonal: Built-in first surface flip-mirror. For astronomical observing, the
internal flip-mirror directs the image to the 26mm Super Plössl eyepiece in the eyepiece holder
at the top of the scope. Touch a lever, and the flip-mirror redirects the image through the
Cassegrain focus at the rear of the scope to an optional #64 T-adapter and T-ring for lunar or
terrestrial photography, or to an optional #932 45 degree viewing angle image-erecting diagonal
for upright and right-reading terrestrial viewing.
* Eyepiece: 1.25” 26mm Series 4000 Super Plössl (48x) specially modified to fit the
scope’s low profile eyepiece holder. The eyepiece field of view is 1.04 degrees, more than twice
the diameter of the full moon.
This Telescope’s Mechanics and Electronics . . .
* Dual fork arm altazimuth mount: The optical tube is aluminum. A full-color photo of
the Orion Nebula (M42) wraps around the tube, adding a visual delight on the scope to the visual
delights you can see through the scope. The rear cell, fork arms, and drive base are durable
metal-reinforced injection-molded plastic that helps keep the cost of the 125PE very reasonable.
While the molded parts of the 125E are quite rugged, a little extra care in setting up and using
the scope might be prudent.
There are three rubber feet on the base of the scope. These allow the 125PE to be placed on a
suitably sturdy tabletop or flat surface for casual computerized observing without having to set
up the supplied full length field tripod.
The mount includes built-in right ascension and declination DC drive motors so the supplied
Autostar computer can automatically track objects. The motors are powered for up to 20 hours by
eight AA batteries (not supplied) that fit into an internal battery compartment in the telescope
base. They can also be powered by optional #541 AC/DC or #607 DC adapters.
When used in the default altazimuth mode on table or tripod, the supplied Autostar computer hand
control moves the scope in any of four directions (right/left, up/down) at any of nine speeds.
The speeds range from 2x the sidereal rate for guiding, up to 5 degrees per second for locating
objects and slewing, plus the sidereal rate for automatically tracking objects under the control
of the computer. No manual slow motion controls are provided – or needed. When set up on the
supplied tripod for equatorial (polar) operation, the Autostar computer converts the right/left,
up/down altazimuth directions to motions in right ascension and declination to correspond with
the coordinates of objects on the celestial sphere.
* EasyAlign with SmartFinder, LNT (Level North Technology): The ETX-125PE contains an
electronic level sensor, an electronic magnetic North sensor, and a high precision internal
clock. These components combine with the Level North Technology software to make aligning on the
sky as easy as remembering your own zip code. Simply take the scope outside and set it up on a
level surface or 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 an alignment star. If the star is not precisely centered
under the red dot in the SmartFinder, you can use the Autostar hand control pushbuttons to center
it to improve the pointing accuracy. Let the scope repeat the process for a second alignment star
and you’re ready to start observing. The LNT system makes using the scope almost as easy as using
a costly GPS-equipped telescope, but at a fraction the price.
* Autostar Software Suite (Astronomer Edition): This supplied software/hardware
package consists of a planetarium/telescope control program and a cable to connect the ETX-125PE
to your PC or laptop. The Autostar Software Suite (Astronomer Edition) is designed to integrate
your telescope with a Windows-based PC or laptop computer for an enhanced range of performance
features.
It includes a planetarium program with a database of 19,000,000 stars and deep space objects to
display on your computer screen. The program has all the display and star chart-printing features
of an advanced planetarium-type software program for stand-alone use when nights are cloudy. If
you connect the scope to your computer or laptop (using either the supplied cable), the program
lets you click on objects in the sky map display on the computer screen and have your 125PE
automatically slew to those objects.
The software lets you control all Autostar functions from your computer or laptop. You can use it
to create observing lists with a simple point and click and download them to the Autostar for use
in the field when you don’t have your computer or laptop with you. You can use it to control your
telescope remotely via the Internet. ”Talking Telescope” software (included) converts the
Autostar’s text displays to synthesized speech and plays it through your computer speaker. An
Autostar Update Tool keeps your Autostar current by downloading the latest system firmware
updates and comet, asteroid, and satellite data from the internet.
The minimum computer requirements for installing the Autostar Software Suite are a PC running
Windows 98SE or better, with 64 MB of RAM, and 100 MB of free hard disk space.
* Adjustable height tripod: The supplied full-length Meade #884 Deluxe Field Tripod
provides a rigid mounting platform for virtually any observing application, astronomical or
terrestrial. It can be used for either standing or seated observing. The #884 has tubular chromed
steel legs and is adjustable in height from 26” to 44” when used in the altazimuth mode. It has a
built-in equatorial wedge with an integral latitude scale and no-tool latitude (altitude)
adjustment for use at any observing latitude between 20° and 90°. The 90° (altazimuth) position
is for terrestrial observation and for quick set-up astronomical observing. Setting the wedge
tilt plate to your observing latitude and aligning the scope on the celestial pole allows more
accurate object location and sidereal rate tracking, but takes more time to set up.
The ETX attaches to the tripod in seconds using two thumbscrews in the wedge tilt plate. The
thumbscrews are tethered and spring-loaded so they can’t be lost in the field. The spreader bar
that holds the legs open is spring-loaded as well, so setting up and taking down the tripod takes
only a few seconds. There are six 1.25” diameter holes cut into the spreader bar to hold 1.25”
eyepieces. The tripod comes with a padded Cordura-style carrying case with carry handle, shoulder
strap, and an external zippered pocket for the spreader bar.
Includes:
* 125mm f/15 Maksutov-Cassegrain optics with standard aluminum coated mirrors and magnesium
fluoride coated corrector plate;
* Dual arm fork altazimuth mount with nylon right ascension and declination bearings;
* Electric slow motion controls and locks on both axes;
* Setting circles (3.5” diameter declination, 7” undriven right ascension);
* On/off switch, 12v input, auxiliary outputs, and computer hand control input in drive base
* Sidereal rate DC servo-motor drive powered by 8 user-supplied AA batteries
* Wide-field straight-through non-magnifying red dot SmartFinder;
* 1.25” 26mm Super Plössl eyepiece (48x);
* Built-in flip-mirror diagonal
* Metal dust cover for optical tube;
* #884 deluxe field tripod with built-in equatorial wedge;
* Autostar computer hand control with LNT (Level North Technology) and built-in database of
more than 30,000 stars and objects;
* Autostar Software Suite (Astronomer Edition) software and telescope to PC cable.
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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-90EC, ETX-105EC and
ETX-125EC; 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 precisely controlled to within +/-1%
of optimal thickness. The result is a dramatic increase in mirror reflectivity across the entire
visible spectrum; at the important hydrogen-alpha wavelength of 656nm. - the predominant
wavelength of emission nebulae - reflectivity is increased from 89% to over 97%.
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-alpha
wavelength of 656nm., total transmission increases from 77% to 93%, an increase of 93/77 or 21%
at all three nitrogen-III and sulfur-II wavelengths of 655nm. and 673nm.- prominent lines in
certain galactic nuclei and in supernova remnanats such as the Crab Nebula- transmission
increases by 21%; ; at the helium wavelengths of 588nm. and 469nm. - strong emission lines in hot
planetary nebulae - total telescope transmission increases by 18% and 19%, respectively; at the
two nitrogen II lines of 655nm. and 658nm. and at the sulfur II line of 673nm., transmission is
increased by 21%. Averaged over the entire visible spectrum (450nm. to 700nm.), total light
transmission to the telescope focus increases by about 20%.
Observing with the UHTC: Meade ETX, Schmidt-Cassegrain, and Schmidt-Newtonian telescopes equipped
with the UHTC present dramatically enhanced detail on the full range of celestial objects - from
emission and planetary nebulae such as M8, M20, and M57 to star clusters and galaxies such as M3,
M13, and M101. Observations of the Moon and planets, since they are observed in reflected (white)
sunlight, benefit in image brightness from the full spectrum of increased transmission. The
overall effect of the UHTC is, as it relates to image brightness, to increase the telescope’s
effective aperture. Image brightness (i.e., the ability to see faint detail) of the Meade 10”
LX200GPS is, for example, effectively increased by about one full inch of aperture.
| Emission Line | Wavelength (nm.) | Transmission: Standard Coatings
(%) | Transmission: UHTC Group (%) | Increase* |
| Hydrogen-alpha (Ha) | 656 | 76.9 | 93.1 | 21% |
| Hydrogen-beta (Hß) | 486 | 75.3 | 85.8 | 14% |
| Oxygen III | 496 | 76.5 | 85.4 | 12% |
| Oxygen III | 501 | 77 | 85.4 | 11% |
| Helium II | 496 | 72.5 | 86.1 | 19% |
| Helium I | 588 | 79.5 | 93.5 | 18% |
| Nitrogen II | 655 | 77 | 93.2 | 21% |
| Nitrogen II | 658 | 76.7 | 92.8 | 21% |
| Sulfer II | 673 | 75.7 | 91.8 | 21% |
* The % increase is obtained by dividing the UHTC-transmission (column 4) by the
standard coatings transmission (column 3).
Effects on CCD Imaging: While the human eye loses sensitivity to light beyond wavelengths of
about 700nm., CCD imaging chips remain sensitive to about 750nm. and longer, wavelengths at which
the reflectivity of an aluminum coating is near its lowpoint. Importantly, however, the UHTC’s
total light transmission at 750nm. is 83%, vs. 72% for standard coatings, an increase of 83/72,
or 15%.
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