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Price: $5,128.00

Availability: Back Order
Product Code: 7300

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An extraordinary innovation in mount design...Now with a new payload!

Recognizing the growing demand for an accurate and stable, equatorial mount with the versatility to carry larger instruments and more complex imaging arrays, we created the iOptron CEM120. It offers the benefits of our revolutionary “center balance” design: stability, accuracy, and smooth mechanical operation, while capable of carrying a payload up to 115 lbs (52 kg). The “center balance” design’s natural stability is due to its focusing the mount along with payloads weight directly over the center of the pier or tripod.

The CEM120's performance is demonstrated by its low periodic tracking error of ±3.5 arc seconds. Along with the stability aspect, the CEM120 features an advanced cable management system consisting of more ports in more locations preventing tangle ups and reducing the chance of fractured cables. It also adds some new features to the CEM family like Wi-Fi and LAN for remote operation and easy to use, reliable clutches on both axes.

Optional heavy duty Tri-Pier 360 and Permanent Pier are available for order.

Optional Tri-Pier adapter for light weight payload ( 8036-120) is also available. It can be modified for permanent pier mounting.
  • A new design, center-balanced equatorial mount (CEM) for maximum payload with natural stability
  • Observatory astrophotography mount ideal for both visual and Astro-photographers
  • Payload of 115 lbs (52 kg) with the mount weight of 57 lbs (26 kg)
  • Easy to use and reliable gear clutches
  • Precision altitude and azimuth adjustment.
  • Precision stepper motor with 0.07 arcsec accuracy for precise GOTO and accurate tracking
  • Polar alignment routine for those who can't see the Pole Star
  • Go2Nova® 8410 controller with Advanced GOTONOVA® GOTO Technology with built in heater
  • High precision tracking with low periodic error (PE)<±3.5 arcsec
  • Permanent periodic error correction (PPEC)
  • 32-channel Global Positioning System (GPS)
  • Built-in WiFi and LAN for remote operation
  • Integrated ST-4 autoguiding port
  • Advanced cable management system with more choices
  • Spring loaded, individual adjustable Losmandy saddle

    Box 1 of 2: #7320
  • CEM120 mount head x1
  • Go2Nova 8407 V2 hand controller x1
  • Hand controller cable x1
  • Counterweight shaft x1
  • Accessory package x1
    Box 2 of 2: #7325
  • 10 kg counterweight x2
Average Rating: Average Rating: 4 of 5 4 of 5 Total Reviews: 5 Write a review »

Permanent Pier
Price: $528.00
Permanent Pier
CW 10kg for CEM120 (Low Latitude)
Price: $228.00
CW 10kg for CEM120 (Low Latitude)
CW 10kg for CEM120
Price: $155.00
CW 10kg for CEM120
Tri-Pier 360
Price: $1,098.00
Tri-Pier 360
Tri-Pier Adapter
Price: $138.00
Tri-Pier Adapter
iPolar™ Electronics Polar Scope
Price: $218.00
iPolarâ„¢ Electronics Polar Scope

  0 of 0 people found the following review helpful:
5 of 5 3 year review June 10, 2024
Reviewer: Paul Gatley from Visalia, CA United States  
I have owned mine since March 2021, purchased new from CA dealer.  I operate the CEM120 as a remote connection in my backyard observatory. I have never had connectivity or slewing issues. I began having USB passthrough cable connectivity issues in Nov 2023. I may order the upgraded cable harness for the unit soon. This is common for USB cables and is expected. Perfect tracking and pinpoint stars. Excellent Mount for an observatory.

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  1 of 1 people found the following review helpful:
2 of 5 Great performance, marred by poor support December 20, 2022
Reviewer: Anonymous Person from Flemington, NJ United States  
When this mount works, it does great. Average guiding when the mount was initially serviced was at a superb .3-4 rms per night. However that great performance slowly started to degrade, and when contacting customer service I was told that it was normal. No, a 30+ arc sec (ra) peak to peak is not normal. Despite how smooth the sine wave is. Having to go from 1.5 to 2 second captures in phd2 to .5 seconds just to be able to guide, with an ra best, at .7-1 rms is a far cry from the previous performance metric.  

IOptron, how does the ra go from a pe of 8 or so peak to peak to 30? All this while always practicing safe operating habits, such as always disengaging the gear locks and locking the axis locks when not in use, or when walking around the mount/balancing.

Paying $600+ for service should have some warranty.

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  1 of 1 people found the following review helpful:
5 of 5 Excellent Heavyweight mount June 5, 2020
Reviewer: Andrew Johnson from Shifnal, Shropshire United Kingdom  
The fixed Losmandy plate is secure but leaves little room for plates with protruding bolts. My heaviest set-up is about 30kg I'm not seeing much flex  loaded. The shaft lock / gear preloading system seems to be about as free of backlash as you can get, even with a heavy load. The guide path seems pretty flat even without PEC playback with this load.
The cable management system is a boon, all of my gear plugs into the saddle plate and I can connect the PC to the static CMS centre ports so I'm not bothered by dangling cable snags on large movements. A USB2 4 port hub seems odd for 2020 but it does the job.   The only other comment I have is that the counterweight bar doesn't seem to have an extension for heavy set-ups so with 30 Kg on the saddle I need 30Kg of counterweights if buying for a heavy set-up consider getting some extra weights.
I put a First Impressions video on You Tube if you want to take a look

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  0 of 8 people found the following review helpful:
3 of 5 3 June 25, 2018
Reviewer: Smith Smith from Chicago, IL 3

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  3 of 3 people found the following review helpful:
5 of 5 Initial Thoughts February 16, 2018
Reviewer: John Crisp from Sylvania, OH United States  
The mount is a beast at 57 lbs without the counterweight bar/counterweights, puts it right on the portability threshold for me. I will primarily use this in a dome in my backyard.

The mount is sturdy, no rough edges or sloppy finish. The machining is clearly well done and the fittings and presentation is very nice and nothing seems cheap or put on as an afterthought. I don't see any evidence at this point of iOptron taking any shortcuts to replace parts with cheap materials.

The internal cabling has shielding to prevent chafing and is a nice touch.

Nice hand controller user interface. Well done as a janky interface can be a major frustration point.
This mount offers great value and quality/capability level for how I intend to use the mount: as an advanced amateur astrophotographer and occasional visual user.

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