this is the main telescope. It is a 12" (305mm) diameter Optical Tube
Assembly (OTA) manufactured by
It has a 3048mm focal length @
F10. The Advanced
optics have the Ultra-High Transmissions Group coatings (UHTC).
it is estimated the
UHTC coatings add approximately a 20% increase
in light gathering. (Meade changed the name to
LX200-ACF (Advanced Coma-Free) and no longer uses the term
to describe the optics. The LX200R and
LX200-ACF are the same expect for the markings.)
The OTA is mated to a Paramount ME a German Equatorial Mount made by the Software Bisque. The OTA is attached using a custom made cradle by Andy Homeyer. The cradle was chosen to hold the OTA because it reduces the amount a flex between the OTA and the mount. The mount is computer controlled although it can also be controlled manually from a joystick. The Paramount ME is capable of carrying up to 150lbs of optical instruments. The program used to the control the mount is TheSkyX Pro.
The telescope's pointing and tracking is extremely accurate, it has a 5 arcsecond Periodic Error cycle before correction. That is important for astro-photography. Unlike the previous telescope used in the observatory (the LX200GPS) that uses spur gears in the Right Ascension and Declination drives The Paramount ME uses belts and pulleys to help all but eliminate the back-lash that plagues scope's that use spur gears.
The scope is balanced using the counter weights attached to a shaft at the opposite end of the OTA. A balanced telescope will track better, as well as have reduced wear and tear on the drive motors. The observatory has the capability to have other telescopes either piggy-backed in addition to the main telescope's finder scope or the mount swapped out for the forked mounted OTA. These scope are listed below:
* Meade LX200GPS Schmidt-Cassegrain manufactured by Meade. The aperture is 10" (254mm) in diameter. It has a 2500mm focal length @ F10. The optics have the Ultra-High Transmissions Group (UHTC) coatings. The LX200GPS series telescopes have been discontinued and have been replaced with the ACF models. The ACF models have different (improved) optics. The LX200 series scopes where "goto scopes". The telescope has a microprocessor with a built-in 145,000-Object Library. Once aligned the scope can be commanded to any one of the 145,000 objects from a handheld keypad. If the telescope is taken to a remote location it can be setup easily. It will automatically find it's latitude and longitude aided by the built in GPS receiver. If in AZ/ALT mode the telescope will then perform an automated leveling procedure, locate true north, then align itself to it's known universe. All with minimal user input.
To help increase the telescope's tracking
accuracy (important for
astro-photography), the nylon spur gears
used in the Right Ascension and Declination drives have been replaced with
Stainless Steel gears. This helps decrease
the telescope's back-lash in both drives. It also reduces the telescopes retrograde motion due to
flexing of the teeth on the plastic gears. The
original factory wet clutch system used on the declination drive
was replaced with a dry clutch designed by
Peterson Engineering. Because of the
additional added weight of items such as the piggy backed guider scope,
solar scope, CCD
camera, microfocuser and aluminum dew shield, a rail mounted balance system was
attached to the bottom of the main scope's OTA as well as a 3.3 lb counter
weight at the aft end of the OTA. The weights totaling approximately 10
lbs are repositioned to balance the scope depending on what accessories are attached
to the scope. It's is important that the scope be as balanced as possible.
balanced telescope will track better, as well as have reduced wear
and tear on the drive motors and gears. The LX200GPS telescope has the capability to
have other telescopes
piggy-backed on the top side (not
including the main telescope's finder scope).
This scope is for stand alone field use.
SV110ED-A Special Edition achromatic refractor. The SV110ED-1 features a
110mm aperture at F7. This features a removable special color matched
filter to reduce spurious color and a 3" dual speed rotating Crayford
focuser. The scope's primary use is as a wide field imager. Telescope
is no longer in production.
* Stellarvue SV102a apochromatic refractor. The SV102a features a 102mm aperture and a 890mm focal length. This scope's primary use is as a wide field imager and guide scope. Telescope is no longer in production.
* Williams Optics Zenith Star 80 mm refractor With its short 480mm focal length, and 80 mm aperture this F6 scope provides great wide angle views of the sky. Beside being a great performing scope I really like the look of this scope. It's deep black finish with gold trim gives it a classy look. Telescope is no longer in production.
Williams Optics Zenith Star 66 mm refractor This is
a grab and go scope. Although not ideal it can also be used as a guide
scope when a
barlow or Powermate is attached to the
eyepiece. This scope can also used for solar viewing by covering the
aperture with a solar filter. Because of its short focal length (388mm) it
provides full disc views of the Sun and Moon and wide angle deep skies views.
* Coronado MaxScope40mm. This special purpose scope is a brass tube, 40mm, 400mm FL scope, dedicated for solar viewing. The scope features a tunable Hydrogen-Alpha filter and a Energy Rejection Filter which blocks the harmful energy produced by the Sun. This scope allows the Sun's prominences as well as the surface granularity. The full 40mm scope is no longer available only the filter is. A full scope is available in 60mm & 90mm.
* Coronado PST CaK. Another special purpose solar scope (no longer available). The Personal Solar Telescope is a brass tube, 40mm, 400mm FL scope, dedicated for solar viewing in the calcium K (calcium III) spectrum. The scope uses a Energy Rejection Filter and built in solar finder. This scope allows the Sun's prominences as well as some surface granularity. The image produced my this scope is rather dim and purple in color.
* Coronado PST H-A . Similar to the PST scope above. The Personal Solar Telescope is a brass tube, 40mm, 400mm FL scope, dedicated for solar viewing in the Hydrogen-Alpha spectrum. The scope uses a Energy Rejection Filter and a tunable Hydrogen-Alpha filter. This scope allows the Sun's prominences as well as some surface granularity.
* Meade ETX90EC: This is a 90mm reflector telescope that uses the Maksutov-Cassegrain design. It has a 1250mm focal length at F15, The nice thing about this scope is it compact size, portability and ease of setup makes it a great travel scope. It can be used for solar, lunar and planetary viewing. The center counterweight on the bottom of the main telescope can be removed and the ETX90's OTA (Optical Tube Assembly) mounted in it's place. This configuration is rarely used as the mounting of the ETX90 OTA causes an imbalance in the main scope's OTA, and with the center counterweight removed, there is no way to rebalance the main OTA. This imbalance would of course have an adverse effect on the main telescopes tracking performance. The ETX90 is normally configured for use on a Meade LXD-55 German Equatorial Mount (GEM) as a portable field scope. Although this scope is considered an entry level scope it has very good optics. The weak point of this scope is the drive.
* Newtonian reflector: A 114mm F8, with a 910mm focal length. The scope was originally a "department store" type telescope made in China and was labeled Infinity 114EQ . It used a poor quality focuser and cheap .986 eye pieces. The focuser was upgraded to a focuser that will accept 1.25" eyepieces. The spider and the mirror were also replaced and a inexpensive AC powered RA motor drive was added. Only the original wood tripod with equatorial mount and tube were retained. The scope is now a great lunar and bright DSO scope. (Note this scope is not a candidate for piggy-back mounting on the LX200GPS OTA but can be attached directly the Paramount's Versa-Plate).
All of the above auxiliary scopes are configured with either Losmandy or ADM 4" dovetail adapter plates. This allows the scopes to be easily swapped and piggy-backed mounted on the LX200GPS OTA or attached directly to the Paramount's Versa-Plate. The Meade LXD-55 equatorial mount has also been fitted with a 4" dovetail plate so it will accept mounting of any of the auxiliary scopes.
To keep the optics clear of dew and frost the LX200GPS OTA has been outfitted with a Astrozap dew shield and series of Kendrick heaters. The heaters are located on the aperture of the main scope, the optical tube of the piggy-backed scopes, the aperture of the finder scope, the eyepiece and base of the main scope's hand controller. The heaters are connected to a "DewBuster" heater controller. The controller is thermostatically controlled and measures the delta between air temperature and the main scope's optical tube, and will cycle the 12 volt DC powered heaters on and off in order to maintain the heaters at the desired set point. Even though the telescope is housed in an observatory, during heavy rains or blowing snow storms, for added protection the telescope is covered with a waterproof cover made by AstroSystems.
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