I have had the Cem70 for a few months now, and got used to it’s quirks and foibles. First, the minuses for this mount. There is only one, and that is the method used to secure the mount to a tripod or pier. The 2 bolts that secure the mount to the pier, are recessed in a deep hole. To make it even worse, the 2 locking plates for the altitude adjustment, lie above these 2 holes. Using a 6mm allen key can be very frustrating at times. I have got used to it now, but wouldn’t like to be fumbling around at a dark site to try and secure the mount. The image below shows the problem.
The rest of the mount is all good news. The balancing of the scope is light years away from the EQ6 I had. Minute adjustments are possible, to get perfect balance, even using a scope as small as the ED80.
The polar alignment in the mount works exceptionally well with the Ioptron software. I use a laptop to connect the polar alignment scope, once connected, polar alignment is done in a few minutes. I don’t use the hand controller, the mount is controlled through the Ioptron Commander remotely, using Windows Pro remote desktop. I did have one small problem with the Meridian flip, whereby the Iopron Commander was overriding SGP, resulting in the mount stopping before the flip, and not executing it. That was an easy fix, so everything is good on that front.
The guiding on the Ioptron is exceptional using PHD2. I don’t run PEC, and haven’t adjusted any of the settings in the Commander software. The mount tracks down to 0.3 RMS on good nights, on bad nights with poor seeing, it can hover around the 0.7 RMS mark. One thing I did find surprising, during a spell of bad seeing, I started to play with the exposure lengths in PHD2 to smooth out the guiding. Normally, increasing the exposure lengths helps with guiding during bad seeing. With the Ioptron, the opposite is true. If I reduce the exposure to 1.5s, the guiding improves visibly.
One of the other pluses is the weight of the mount. It is a large mount, but surprising light. It could be used quite easily on a trip to a dark site. The case it comes in, is a relatively small 50cm x 40cm x 22cm. So would fit quite easily on the back seat of a car. The overall build quality on my mount is very good. Adjustment of the belts is straightforward. All the USB and power ports work on the mount. I power the mount through a Pegasus Astro Power box, I wouldn’t even need that, if my dew straps were not connected to it. The Lan connections provide a very stable connection. I hard wire the Lan connection, and have never lost signal to my PC.
Overall the mount is very good quality. Definitely worth buying, if you are in the market for a decent mid range mount. Mine is attached to the Tri-Pier, which provides a rock solid foundation for imaging and quite strong winds don’t seem to affect guiding at all.