iOptron CEM70 Review

[AstroRuz]

FLO sent me this beast of a mount for review, and after a few months use I've finished said review. If you don't want to read, then scroll to the bottom to see the video. If not, let's go.

From the top, the dual type Vixen/Losemandy type puck, and at the back of mine it had 3 5521 type power ports for powering equipment, and 3 USB ports (2 powered) for connecting to the internal USB hub network. Whilst I didn't exactly use this network, it's still very handy to use, especially being on the puck - it means you don't have to worry about any slack on your cables and they won't pull. A handy feature. The power ports seem to be of a different type to 99% other astronomy hardware though, which means you'd need to get different connectors, a major inconvenience which still will make itself known later.

The mount includes an iPolar system, which is absolutely awesome. Sure the UI looks like it's straight out of Microsoft Paint but it's certainly function over form as it's quick and uses plate solving to align. This means you can polar align even with a semi-obstructed view to the pole. It's powered by a USB2-B port at the back of the mount with no need for external power. There is no manual polar scope on the mount so a computer is a must for polar alignment.

The carry capacity of 31.8kg is a hefty amount, though it's advised to not exceed 21kg for astrophotography. I never loaded it up with this much equipment however the sheer build quality and performance of this mount leads me to have no concerns whatsoever about using that much weight, or even all the weight. It's always advised to use underneath the stated maximum capacity anyway.

The altitude adjustment knob is a hefty coarse worm gear style affair. Embossed with the iOptron logo. It's a nice way of adjusting, especially when coming from GEM mounts where you have to undo/do up two individual bolts. However on my mount it was let down by an abhorrent squeak it made when raising it whilst the mount was loaded up. When going down in altitude sometimes the gear would jump a bit and let the mount down even further than I wanted. Azimuth adjustment was fluid and great.

The control panel includes its power port, power switch, hand controller port, ST-4 port and the USB port. The USB port can be used to control the mount via computers, and is also the other end of the internal USB network. It is USB2-B. 

A major issue I found was the power port. It wasn't the standard type DC centre-positive tip style that all my other astro equipment used. IT's also a standard female type port, whereas I would've liked to have seen a screw type connector for this price point. But yes, the biggest gripe was the different style port, which meant I couldn't power it using my power box (without getting more cables), and had to use the supplied plug.

The carry case is a substantial and very sturdy box. It's foam cutout and very tight in holding the equipment. All but the counterweight goes into this box and I believe it could really survive quite a harsh fall. It's very well built.

Slewing with the CEM70 was quick and fluid, it was also quieter than I was anticipating for such a large bit of machinery. Using its own dedicated software through the laptop was intuitive and there was little to no learning curve. The axis clutches, whilst using a small switch, feel solid and substantial with a nice meaty clunk when engaged. One lock position is the EQ Home position which makes life a lot easier.

When guiding, I was regularly getting values of 0.4-0.6" total error. This enabled me to take extremely long exposures if I so desired, though I mainly did  5 minutes, I was able to do 10 under testing. Unguided (just sidereal tracking) I was only able to achieve 2 minutes before trailing was found with my Evostar 80ED (reduced to 510mm) and ASI 071mc Pro. Now in full admittance the mount was unbalanced as the Evostar package was too light for the mount. 

The counterweight, if moved too high up the bar, will strike the body. So you would need to buy a lighter weight if you wanted to balance a lighter load on the CEM70.

Also when attaching it to a tripod or a tri-pier, you do need to bolt down 2 spring loaded bolts down with the supplied allen key. Now this is a bit fiddly and adds several minutes to the setup and tear down times. Though I suspect iOptron made this mount with a permanent setup in mind so if you're putting this into an observatory then this won't be a problem. For me, who setup and torn down the rig each night when using it, became a bit of a chore.

Overall I found the CEM70 to be an extremely capable mount with a lot of features. Whilst there are niggles that detracted from the user experience; the altitude gear squeak and the non standard power ports. Other features improved the quality of life and user experience enough to vastly outweigh the drawbacks. The iPolar system is particularly capable and excellent, the carry capacity, build quality also and guided performance, as well as the internal USB hub. 

I think this would be a nice investment if you were looking to mount larger scopes on, or decking out an observatory. I can't afford one but if I was making my own permanent setup I would severely consider buying one. 

If you're interested you can find more information at the links below (if you did buy through these links, I'd earn a few pennies to help support these reviews).

iOptron CEM70 w/o iGuider: https://bit.ly/CEM70

iOptron CEM70 w/ iGuider: https://bit.ly/CEM70iGuide

iOptron Tri-Pier: https://bit.ly/CEM-Tripier

 

Thanks for reading everyone. What are your thoughts about this mount? I hope my review has been helpful for you  clear skies all, keep looking up and keep them cameras clicking.

[nfotis]

If I understand correctly, this is a new design?

Only time will show if it's reliable enough for such a large amount of money.

I guess that the tri-pier is a necessity for this heavy mount.

N.F..

 

[pete_l]

5 hours ago, nfotis said:

I guess that the tri-pier is a necessity for this heavy mount.

That's a good point. Since the CEM70 is only the mount head, without a tripod or pier, any review about the performance won't be about the mount itself. It has to be for the combination of mount + extra-cost tripod.

[david_taurus83]

Nice honest review Ruzeen. Pointing out the niggles unlike other "reviewers". Looks like a nice mount still.