I purchased the mount head for a wide field imaging rig.I combined this with a WO Redcat and ASI2600MC and also a TPO UltraWide 180 f/4.5 Astrophotography Lens. I also added a ASIair pro for a simple portable rig. I received the mount and had it in storage for a few months due to weather and work.I got it out in the end and put it together.I didn't know that I wouldn't get a mount cable to update the firmware.I also didn't get the weights with the mount but I did know this. I did get the 1.75-Inch LiteRoc Tripod with it but the mount head did not fit so I had to contact ioptron and got the one that did. At last I managed to get some testing done and found that the guiding was terrible. I spent some time looking into it and at one stage I was going to send the mount back to OPT but after some careful digging I changed the guide settings in PHD which made the difference and in the end I was able to get very good guiding and when turning on PEC I can get an error of around .40 to .70 depending on the night.I have attached a PHD screenshot. The Ipolar worked well and was easy to use.I don’t much care for the software but overall no issues and on a good night with a wide field setup you can easily get a 5min exposure unguided. The go-to works ok but it has a tendency when you do a 1 or 2-star alignment to go miles away from the alignment star even though you have good polar alignment.I haven’t figured that out yet but I am hoping that a firmware upgrade will fix this(I had to order the cable from ioptron)This can cause the alignment to fail.But most of the time its ok.After a 2 star alignment most objects are somewhere in the field of view.However when using the ASIair the alignment is perfect right on centre every time. Due to a software bug that has not been fixed by ZWO or ioptron (at the time of writing this review )the mount normally fails to connect to the ASIair.After spending around 20 hours of trouble shooting I still haven’t corrected the issue.This is the main reason for giving this mount 4 stars. Currently I have not tried a heavy telescope but plan to try a C11 so that will be interesting to see how that goes. Attached are a couple of 1X15min exposures taken with the ASI2600MC no calibration files and only stretched a bit not much else done.These were just to test the guiding. But overall it is well made and doing adjustments for polar alignment is o.k. If you want a pretty portable and easy-to-use mount this might be the way to go.But until software bugs are fixed I cannot recommend the ASIair pro to work in conjunction with the mount.

Mount appears to be very well made. Hand-controller firmware required update to be useable. It did not even recognize the mount as shipped. Luckily, the documentation for the update process is decent (serial port is required). iPolar is awesome after figuring out the alignment procedure (starting position is slightly ambiguous in the documentation). The unit I received seems to be an updated model. The main power input is 2.5mm x 5.5mm, which means the more common 2.1mm x 5.5mm won’t work (there are very inexpensive adapters available). I bough an iOptron’s DC car charger cable separately thinking that would work, but it came with 2.1mm x 5.5mm, so they haven’t quite worked out a variant for the new version of the GEM45. The AC power supply shipped with the unit works, though. Also on the new model, the dual *****/Losmandy saddle has been improved and no longer requires flipping over blocks to switch from one style to the other. The new system worked great for both Losmandy and ***** dovetails and once secured, I had no slippage at all. I did have to remove, clean and lubricate the thumbscrews for the saddle, though. As shipped, they had residual metal dust in the tapped holes and when tightening the thumbscrews, you could feel a terrible grinding on the threads. After removing the thumbscrews and spring-loaded pinch blocks, I blew out the tapped holes with compressed air and a lot of debris came out. I applied a light grease to the threads after cleaning and then all was good. First light, mount performed great. Polar alignment stayed “green” for hours, and after a 1-star alignment, slews seemed right on. 2-minute, unguided exposures yielded round stars with 100mm f/9 apo. My setup balanced nicely with an 11 pound counterweight, but the weight was close to the end on the shaft. Heavier setups (over 20 lbs) will probably require more counterweight. If it weren’t for the work required to get the saddle cleaned up and hand controller firmware updated to work at all, I would definitely give 5 stars.