This telescope is checked, measured and adjusted if necessary before delivery. The focuser will be optimized. Upon request, you will receive a meaningful quality certificate from your telescope (test report with star test, Ronchi, adjustment, with individual serial number) included! Please specify with order!

Examples of our test protocols: test recordings
How we adjust: About us

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The 7 "(18 cm) Maksutov-Cassegrain telescope with an aperture ratio of 1:15 offers high-contrast planets and lunar landscapes, perfect for planet photographers and visual observers.

Celestron CGEM II 700 Maksutov-Cassegrain - 180 mm telescope on GoTo mount

♦ With 180 mm aperture, 2700 mm focal length and 3.1 ° field of view

♦ The high-quality StarBright XLT coating from Celestron ensures maximum light transmission.

♦ The CGEM II, successor to the popular CGEM mount, with a load capacity of 18 kg offers a modern design and carries the 700 Mak safely and vibration-free.

♦ The drive system, consisting of low-cogging DC servomotors with integrated optical encoders, steel worms, which are guided by sealed precision bearings, and brass worm wheels, ensures smooth and precise swiveling and tracking.

♦ Including accessories: 2 "Visual Back eyepiece tube, 2" diagonal with 1.25 "adapter, 28 mm eyepiece (2"), 8x50 viewfinder



Celestron CGEM II 700 Maksutov-Cassegrain on GoTo mount
The CGEM II 700 Maksutov-Cassegrain telescope (CGEM II 700 Mak) is a specialist for detailed, high-contrast observations of small celestial objects such as the planet. With the Maksutov-Cassegrain tube, the robust equatorial mount and the stable tripod, this telescope system enables incomparable planetary observation and detailed images of the lunar surface, including its craters and seas. Maks can include can also be used for smaller, weaker deep sky objects such as globular clusters and planetary nebulae. Astronomers near the city will appreciate the Mak's ability to create more contrast in celestial objects. Transporting the entire system is also not a problem. The telescope can be dismantled into individual handy parts without tools: optical tube, mounting head, counterweight rod, counterweight, hand box, tripod and storage plate.

Optical design of the Maksutov-Cassegrain
The Mak is a catadioptric telescope, i.e. the optical design includes both a lens and a mirror. The light coming through a Mak goes through the corrector lens to the primary mirror and back to a spherical secondary mirror before it hits your eyepiece. The images are bright, sharp and practically free from chromatic aberrations.




The optical design of the Maksutov-Cassegrain offers several unique advantages. Instead of a secondary mirror, the Mak has a "secondary spot" with a reflective coating that is applied directly to the inside of the corrector plate. For this reason, the telescope does not need frequent collimation like a Schmidt-Cassegrain. In addition, the "secondary spot" is significantly smaller than a conventional Schmidt-Cassegrain secondary mirror, which enables the characteristic high-contrast image.

With Maksutov-Cassegrain telescopes, it is important to note that the larger, heavier Maksutov corrector plate takes longer to cool down and adapt to the ambient temperature than a Schmidt-Cassegrain with the same opening.

CGEM II mount & tripod
The CGEM II is a robust equatorial mount that can carry the telescope without vibration. With a payload of 18 kg, it can easily handle the 7 kg of the 700 Mak tube, so that there is sufficient payload for your camera and all accessories. The sturdy, height-adjustable tripod has tripod legs made of steel with a diameter of 2 "and graduated markings to quickly and easily adjust the legs to a uniform height. The 700 Mak is mounted directly on the CGEM II with the 3" CGE dovetail rail.

The mount is packed with features that make working with the 700 Mak easy. The fully computer-controlled mount automatically moves to each of the more than 40,000 astronomical objects, as it was selected from the database of the NexStar + handheld controller.

The drive system of the CGEM II was developed taking into account the requirements of astrophotography and tracks precisely. At the heart of the system are the DC servo motors with integrated optical encoders for quiet, even operation. They have a very low starting resistance, so there are no voltage peaks that can overwhelm the power supply. The motors drive precision-mounted steel drive worms that act on brass worm wheels. These components also help ensure that the drive works smoothly, quietly and precisely.

To track objects in the night sky, the mount must first be arranged. Thanks to the built-in All-Star Polar Alignment, northing is not a problem, even without a view of the celestial pole - the polar finder is superfluous (a polar finder is optionally available.) The best thing is that the set-up is usually completed in less than 15 minutes can be, even without a clear view of the North Star.

All classic mounts have a certain "periodic screw error", which is caused by tiny gear irregularities. To prevent this, the CGX has permanent periodic error correction (PPEC). For this purpose, the periodic error is recorded and saved once, then the control software of the hand controller automatically corrects the periodic screw error. For even higher tracking accuracy, the mount also has a special autoguider connection to connect an autoguider camera directly to the mount.

The best conditions for observation are when celestial objects are at their highest point in the sky, the so-called meridian. But some parallactic mounts have difficulty tracking close to the meridian because they have to do a "meridian flip": the telescope has to be turned. CGX does not suffer from this problem because tracking is possible beyond the meridian and no meridian flip is required. It tracks up to 20 ° over the meridian.

Together with the NexStar + hand controller, the mount also has dozens of other functions. This includes:

♦ Several methods of aligning the mount in the night sky
♦ A swivel speed of up to 5 ° per second
♦ Can be used in the northern and southern hemisphere
♦ Autoguider connection
♦ Idle state so that the mount can be switched off without losing alignment.
♦ Continuous firmware updates

In addition to the autoguider connection, the CGEM II also has other connections. The hand control has a USB 2.0 connection to control the mount with a PC and optional third-party software. There is an AUX connection on the mount for optional accessories such as StarSense AutoAlign or the SkyPortal Wifi module.

Cable management can become a challenge in astrophotography: the camera requires a cable, another leads to the power supply to the mount, and the cables from the computer connection and autoguider - to minimize problems with the cable routing and to avoid unwanted problems, the mount is for worry-free remote operation internally wired. This also eliminates the need to connect or disconnect an external declination motor cable.


Optical design: Maksutov-Cassegrain
Opening: 180 mm (7.08 ")
Focal length: 2700 mm (106.3 ")
Aperture: f / 15
Focal length and plug-in size eyepiece: 28 mm 2 "eyepiece
Magnification with the included eyepiece: 96x
Resolution (DAWES): 0.52 arcseconds
Resolution (RAYLEIGH): 0.64 arcseconds
Viewfinder: 8x50
Zenith mirror: 2 "with 1.25" adapter
Highest sensible magnification: 420x
Lowest reasonable magnification: 67x
Limit size: 13.9 mag
Light collecting capacity (to the human eye): 661x
Secondary mirror obstruction: 40 mm (1.57 ")
Secondary mirror obstruction rel. to the diameter: 22%
Secondary mirror obstruction rel. to area: 5%
Remuneration: StarBright XLT
Tube length: 57.15 cm (22.5 ")
Tube (material): aluminum
Tube weight: 8.6 kg (19 lbs)
Mount: Parallactic mount (motorized)
Motor drive: DC servo motors
Swing speed: 9 swivel speeds - maximum speed 4 ° / second
Tracking speeds: sidereal, sun and moon
Tracking modes: EQ North & EQ South
Power requirement: 12 V DC, 3.2 A
Number of AUX ports: 2 aux ports (1x hand controller port and 1x AUX port for optional accessories)
USB port: Yes, on mount and hand controller
Guiding port: Autoguider port
Alignment methods: 2-Star Align, 1-Star Align, Solar System Align, Last Alignment, Quick Align
Screw error control (PPEC): yes
Hand control box: 2 lines x 18 characters backlit liquid crystal display, 19 LED backlit buttons, USB 2.0 connection for PC connection
Database: 40,000+ objects, 100 custom programmable objects. Extended information on over 200 objects
Software features: Celestron's Starry Night Special Edition software, SkyPortal app
Carrying capacity (kg): 18 kg (40 lbs)
Pole height adjustment: 15 ° - 70 °
Counterweights: 1 x 7 kg (17 lbs)
Tripod Leg Diameter: 50.8mm (2 ") heavy duty steel tripod with markings for quick height adjustment
Height (mm): 134.6 cm - 165.1 cm (53 "- 65") - mount and tripod
Axis weight: 18.14 kg (40 lbs)
Total weight: 41 kg (90.5 lbs)