iOptron CEM70 Center Balanced Equatorial GoTo Mount with iGuider
iOptron CEM70 Center Balanced Equatorial GoTo Mount with iGuideriOptron CEM70 Center Balanced Equatorial GoTo Mount with iGuideriOptron CEM70 Center Balanced Equatorial GoTo Mount with iGuideriOptron CEM70 Center Balanced Equatorial GoTo Mount with iGuider

iOptron CEM70 Center Balanced Equatorial GoTo Mount with iGuider

  (4 Reviews)
✓ 2 year warranty


Out of stock due 10-15 working days

About this product

Model:  iop_cem70_C70AG
Part Number:  C70AG

Building on the success of the iOptron CEM60 centre balance equatorial mount, iOptron have introduced the new CEM70.

This model features iOptron's integrated 'iGuider' guiding scope and camera. 

Retaining the inherent properties of the centre balance design, this relatively compact mount provides an impressive 70 lbs (31.8 kg) payload capacity, precise GOTO pointing and accurate tracking (PE <±3.5 arc-sec) so will appeal to both both visual astronomers and astrophotographers. 

An impressive features list includes an internal iPolar electronic polar scope, easy lock drive gear engagement (levers large enough to use with gloves) and an integrated 'iGuider' guiding scope and camera. 

It also features an advanced cable management system for the mount, iPolar, guider, and camera. 

Note: The tripod/pier shown in photos not included but is available separately. 


  • A new design, center-balanced equatorial mount (CEM) for maximum payload with natural stability
  • Ideal for both visual observation and astrophotography
  • Payload of 31.8kg / 70lb  with the mount weight of 13.6kg / 30lbs
  • 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
  • iPolar electronic polar scope
  • Go2Nova® 8407+ V2 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)
  • Onboard iGuider autoguiding system
  • 32-channel Global Positioning System (GPS)
  • Built-in WiFi for remote operation
  • USB3.0 connection
  • Integrated ST-4 autoguiding port
  • Advanced cable management system with more choices
  • Spring loaded 8" Vixen/Losmandy dual saddle
  • Hard case

Go2Nova Hand Controller 8407

  • 200,000+ object database
  • 8 line, 21 character back lit large screen LCD
  • Low temperature operation as low as -20ºC
  • User friendly interface
  • 9 speed slew control with quiet mode
  • Large object database
  • Serial port for firmware upgrade


What's in the box

  • Mount head – with iPolar electronic Polar Scope & onboard iGuider guiding scope
  • Hand Controller (HC) – Go2Nova® 8407+
  • Counterweight – 21 lbs (9.5 kg)
  • Stainless steel counterweight shaft
  • Built-in GPS module
  • Hand controller coiled cables
  • USB cable
  • AC adapter – 100-240V (DC output 12V/5A)
  • Hard case
  • Quick Start Guide
  • Tripod NOT included 


Mount Center-balanced Equatorial Mount (CEM)
Payload 31.8kg (70lbs), exclude counterweight*
Mount weight 13.6kg (30lbs)
Payload/Mount weight ratio 2.33
Material All metal
Latitude adjustment range 0°~ 65°
Azimuth adjustment range ± 4°
PE (by encoder) < ±3.5 arcsec**
Worm period 348 sec
Right Ascension worm wheel Φ151mm, 248 teeth
Declination worm wheel Φ151mm, 248 teeth
Worm Φ21.2mm
Right Ascension axle Φ55mm, steel
Declination axle Φ55mm, steel
Right Ascension bearings Φ80mm
Declination bearings Φ80mm
Counterweight shaft Φ28x 415 mm (SS, 1.9kg)
Counterweight 9.5 kg (20 lbs) x1
Mount base size Φ152mm
Motor drive Precision stepper motor w/128 micro-step
Resolution 0.07 arc seconds
Slew speed 3.75°/sec (900x) max.
Hand Controller Go2Nova® 8407+, 8 line 21 character LCD
Power requirement DC 12V, 5A (5.5mm/2.5mm plug)
Power consumption 0.6A(Tracking),0.8A(GOTO)
Polar Scope Internal electronic polar scope, iPolar
Meridian treatment Stop (0-10° pass), auto flip
Zero position Automatic zero search
Park position Horizontal, vertical, current, alt/azi input
Level indicator YES
Dovetail saddle 8" Losmandy D & Vixen
Guiding port ST-4
Communication port USB3.0, Wifi
Cable management 2xDC12V (3A), 3xUSB3.0, 1xDC in/2xDC out, iPort.
1X USB input for mount, iGuider, iPolar and more
Guiding scope/camera Built in guiding scope and camera, iGuider
Operation temperature range -20°C ~ +45°C
Hard case YES
Pier/Tripod Optional LiteRoc tripod or pier
Warranty Two year limited


* iOptron's quoted max' payload is a guide only. If you will be using the mount for astrophotography (or your telescope is unusually long or large) we recommend the quoted max' payload be reduced by 1/3rd. 

Downloads / Manuals


Quick Start Guide 
Instruction Manual 
iPolar Operation Manual 
iGuider Operation Manual 


Download Latest Firmware 
iPolar Software 
FTDI VCP Driver, or go to FTDI Chip website to download the VCP driver

iOptron Telescope ASCOM Driver:

Install ASCOM Driver and Commander 

Customer reviews

Average Rating (4 Reviews):  
Write a Review and share your opinions!

Rating (max 5):  
Very good after minor setup issues
24 February 2022  | 

This was bought as a customer return in a recent FLO special offer wave and after some initial gremlins were dealt with I am delighted with it. I had to rotate the ipolar camera through 90 degrees to match azimuthal adjustments to left right screen motion in the ipolar app, and I needed to fiddle with the USB3 cable choice to stabilise connection with my mini PC. Then it all came to life.

The iguider works very well at shorter focal lengths. It is a pain to focus but I got it sorted and it has not needed re-doing. It is perfectly fine with my camera lenses, 61EDPHII and my APM 107mm reduced to 525mm. Mount control, ipolar and iguider all work stably through the single USB3 connection to my mini PC.

For longer focal lengths I use a big 80mm guide scope or an on axis guider. The ONAG has been delivering total rms error down to about 0.35Ē with the 70G which is giving me small round stars (errors only slightly higher in RA than DEC) with my C8 SCT at 1450mm. I do have some backlash of around 600mm on my DEC and plan to tweak the meshing and check the belts at some point, but given that PHD2 correction sorts it out I havenít bothered yet.

With a wifi enabled mini PC by the mount I have not used the wifi much, but find the usb hub excellent. Iím mainly using usb2 gear through it, and have had my external guide cam, filter wheel and focus motor all going through it, all working through a single usb3 cable to the mount along with ipolar and mount control (and iguider when not using an external guide scope).

Iím glad I got the G version now, having agonised over whether it was useful over the vanilla CEM70. The only remaining foible is the mount forgetting its time zone when switched on. Takes seconds to fix, though a bit odd.

I really love this mount. Iíve started controlling it with NINA as galaxy season gets under way and it just slews to small galaxies in usually two solves (max 3) with ASTAP at 1450mm and holds them firmly, guiding with errors well below my pixel scale.

I strongly recommend you use a Windows based ASCOM interface to control this mount in particular. Ipolar and iguider work great in that environment, you get the power of full PHD2 (PPEC algo and backlash correction as well as guiding assistant) and no brand limitations or USB incompatibilities. Ipolar is a fantastic and underrated tool, allowing camera calibration to high precision and routine PA quickly to less than an arcmin accuracy.

One nice little feature is that the RA axis can be locked with an Allen key with the RA axis ďclutchĒ unlocked. So with the DEC also unlocked I can carry the mount pre attached to the tripod pier from my garage to my imaging location. So it can all be moved around easily without damaging the meshing. Bigger risk to oneís back and muscles perhaps, but fine over short distances and really saves some hassle if like me you have to set up and take down each session.

Rating (max 5):  
A fantastic mount for the money- very well suited for the Celestron RASA 11
28 February 2021  | 

I purchased the CEM70G before Christmas but had to wait 3 months before I could use it with a new V2 RASA 11" that arrived in the last week.

I ordered the mount with the Tri pier and 3 additional counterweights as the RASA is a beast at over 20 Kgs. The mount easily handles this weight. The mount is light at only 30 ilbs and comes packed in a very sturdy aluminium case- not even my Paramount at 10K has that as standard. I would always advise buying more counterweights as it is always a bit late if you've not ordered and need the weight!

Cable management is good but be aware that if you use the smaller vixen rail this will block the cables exiting through the saddle- so you will not be able to use. I built an ADM top & bottom D-rail assembly for my Parallax rings so I was able to slip in the D-plate and rings and thus use that as an easy way to mount the RASA. The saddle locks work very well- they are exceptionally tight and well machined.

I spent a few days getting to know the mount. It is very easy to balance as the axis's move exceptionally smooth- I suspect even smoother than my Paramount MX+ which costs 3 times as much.

I pointed the RA axis at the pole using a compass and set the elevation at 52.5 using the vernier scale on the altitude adjuster. I then calibrated the polar alignment using the I-polar scope. One thing the manual does not mention is that the circle & cross goes green when correctly dialled in.

I'm using an Altair 60 mm RACI guide scope on the top rail fitted to the rings & use the Lacerta MGEN3 guider which guides fabulously- as it is a dedicated guide computer & camera

I'm using a NUC computer under the tri pier and is a USB connected device using the SKYX pro software. It is easy to zro the mount, sync on an initial star the after that the SkyX controls the mount- I simply plate solve to a target.

I can't yet say how good the tracking is as I use the RASA which has a short focal length so it is forgiving of errors- however I get really round stars which suggests tracking is good.

The features of the mount are what sets this apart, built in GPS & Wifi, integrated USB3 hub and excellent cable management- you really can't go wrong especially with the built in 30 mm guide camera and Ipolar as well as through the mount power connections.

You need to ensure you use a really good power supply. I use the mounts 12 V 5 aMP PSU to power my camera through the mount connected power and have a seperate 30 AMP 12 V PowerWerx PSU to power the mount. All other accessories share this PSU and I have a full rack of Anderson Power Pole 12V connectors for all the ancillary devices.

I've not really experienced anything bad with the mount. The Tri pier center colunm is easily scratched but If you are aware you can mitigate this by putting felt inside the locking rings to prevent scratching. I have 60 ilbs of weights and a 45 ilb load on the mount and it tracks and slews beautifully provided you pay attention to balance in both axis.

I highly recomment this mount and as always great service from FLO.

Rating (max 5):  
Excellent basics, some niggles
17 November 2020  | 

I have had one clear night to use this mount so these are my initial reactions.

The mount is heavier than I expected and needs a bit of technique to get out of its rather nice box. It came with no instructions at all, and missing the firmware update RS232 cable but FLO kindly sent me one. Instructions are available on the web, and commissioning went smoothly. I really like the mechanical design with two RA bearings. There is no perceptible backlash when pushing the axes by hand. Both axes are very smooth with very little friction. The quality of castings looks really good and the balance shaft is stainless steel. There were early reports that the wiring in the centre of the mount was a bit of a mess but these wires are now in two neatly sleeved bundles. There are two independent routes to get 12v from the base to the scope through the mount. This makes wiring ancillaries much easier.

First operation went more easily than anticipated. The iPolar program makes polar alignment relatively easy and the adjustments to the mount are smooth. I used a 242mm focal length 50mm aperture guide scope and ASI290 guide camera. I let PHD2 set the parameters and it reported good backlash and immediately guided at 0.6 arcsecs RMS. The mount makes a quiet ticking when running. I measured the worm error, using the PHD logs and PECPrep, as 2.9 arcsec RMS, which is just what the included calibration sheet showed within experimental errors from my rapid measurement. PHD2 reported the polar alignment error as 0.6 minutes of arc but this is prone to effects other than polar alignment so is probably less.

Not everything is perfect. The built in iGuide system uses a 20mm objective and 120mm focal length guide scope. Itís relatively small focal length lens will limit performance but there is a bigger problem. The scope can only be focussed by using a knurled knob on the casing, but this is not a screw adjustment as I expected but just loosens the internal camera. You have to slide the knob to focus. The depth of field is around a tenth of a mm so focusing is very difficult and will probably limit its use. I did guide with it getting 0.8 arcsecs RMS but had to use a zero magnitude star as I couldnít focus well enough to use dimmer ones.

The mount uses wi-fi and connecting to the mount using it is just the same as using a cable, with one important difference. The ASI290 camera will not download images over wi-fi, I think because the data rate is too low. I did e-mail ZWO to ask what data rate is needed but they just confirmed that their cameras donít work over wi-fi.

I would recommend this mount. The basics are very good. You get a lot for your money. A mount with this load capacity and performance but made in the US or Japan would cost two or three times as much. The G option gets USB3 rather than USB2, better cable routing and the iGuider and wi-fi. Whether this is worth it is, I think, a personal decision.

Rating (max 5):  
Very impressive
27 July 2020  | 

Ok, so this is my first product review for a major item. First of, this was heavier than I anticipated, but then again Iíve been used to a Sw star adv on a typical tripod using a Wo ZS71ed. It is still very much portable for star parties or seeking out dark skies. This is my very first own goto mount, I have once borrowed a Celestron AVX and because of this, led me to purchasing the CEM70g. The quality of the build, the precision of the engineering is fantastic. It has a great sturdy feel about it and set up onto the tri-pier was simple enough. Initial set up of the mount is very straight forward, just switch it on, the gps does its thing almost instantaneously and before you know it youíre good to go. I had to adjust the time but that was it. So Iím just trying to link the WiFi of the mount to SS6 pro on macOS but am having some issues regarding the mount due to not being on the SS6 mount list, it needs to have the ip address and port put in manually. I have had immediate success using the Usb3 port with a usb to thunderbolt adaptor and choosing the Cem120 option. This allowed control of the mount via SS6. As Iíve gone at the deep end with a mount that has iPolar & an iGuider, Iím slowly getting round to trying these features out and will review this again soon. Iím looking forward to setting up the scope with my ASI 183 c Pro using the usb3 and power ports for the cable management. I will review again with pics hopefully but in general, I feel this is a great mount that will serve me well for years to come. If the cem60 is anything to go by, this should be a very good replacement/upgrade. Thank you Flo for your advice as always & your support to date for helping with the purchase of my first goto mount.


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