Razvan

If you want precision, you can align the previous night and leave the mount untouched.

A couple of more notes I forgot to include in my previous message: I found it useful to level the tripod very well (I use the iPad, sitting flat on the plate before putting on the mount; the Polar Scope Pro app has a bubble level among other things - there are many other apps offering such a level). If the mount is not level, aligning works equally fine but without a counterweight and with the clutches unlocked and no other friction applied, the scope will rotate to come on the lower side. I don't know how come the mount has such a low friction, it almost feels like it uses magnetic levitation inside 🙂. To clarify: during normal observing, the clutches and friction knobs will be engaged. Given that the mount and tripod hold everything without the counterweights, I like the absence of the bar & weights from an aesthetic perspective. centering stars during alignment was painless as there's no backlash at all (not even from the slo-mo controls - I'm saying this because a couple of years ago I had a Vixen Porta II whose slo-mo screws never kept the handles tight and had quite a bit of play). So for the final movements, you don't have to always come from the same direction like with less precise mounts. speaking of balance, I still have to figure out what's the best way to balance the OTA with eyepieces of different weights (my heaviest is a Delos 14mm, the others are lighter Plössls - also have a PowerMate 2.5). One option is to balance for something in between the extremes. Another is to balance for the eyepiece used most of the time. A third option is to leave the eyepiece end heavier since it's always going to be stay lower. Suggestions are welcome if you have experience with this. an observation: before the last sessions I had forgotten to enable DST (we already switched here in Canada) and only realized after I made the 3-star alignment (my Nexus DSC came from Rowan with the newer firmware offering this option). I found that the model was accurate and thought Nexus must be using the UTC time from GPS. The manual says that the 2-star alignment doesn't use the location, date or time for alignment and pointing. I guess the 3-star model doesn't use that either. I found this interesting, all the other mounts I used in the past were sensitive to the time zone, I thought the math would be the same. also noticed that once I used "Find from Planetarium" once with SkySafari, I didn't have to select this option from Nexus but simply tap on the new target in SkySafari and Nexus immediately showed the slewing directions. This made it more convenient as I didn't have to press buttons on Nexus at all from my sitting position, just select the target on the iPad which was close on a small table. For slewing I did need to look at the displayed arrows Nexus, of course, but I guess I could look at the iPad screen. Nonetheless, I enjoyed slewing until Nexus showed the target was supposed to be in the centre and only then looked to find it there indeed. I found this precision reassuring when identifying a couple of asteroids. The experience with less precise alt-az mounts in the past was different: I knew slewing got me with the target somewhere in the field, but then had to compare the view with the planetarium to figure out which dot was the one of interest. using SkySafari reduced the need to have the observing list written on the Nexus' SD card. I'll probably still do it as a backup. BTW, I think Nexus doesn't normally write to the SD card so reliability is higher. From using a couple of Raspberry Pi of different generations, I got used to needing to reformat the card after losing power during card writes - this corrupts the file system. For important trips, I'll probably have a backup card with the same contents. Cards are more reliable now, but it's cheap insurance. Hope this helps, Razvan

I had the opportunity to use the mount a few more times since my last message, this time out at a dark site (a TSA-120 on a Berlebach Planet, no counterweight). A couple of comments: since it has no motors, the utter silence is perfect for visual observing, there's no humming, whirring or anything that reminds me of a mechanism. With a 120mm refractor, using slo-mo controls was not a problem, there was time to observe an object before moving it. also because it has no motors, I was able to observe targets very close to the zenith and then step away without worrying that in a few minutes, the scope might hit the tripod legs. I find the lack of a need for power supplies and cables to be very relaxing (although I will need them when using dew heaters). I also do astrophotography but find since the Nexus' battery lasts so long, I can go completely off the grid for days without worrying about power. In fact, I think that whenever I go to a Bortle 2 site, I'd rather observe visually many objects than image one or two per night as a normal imaging session is wont to be like. I also like the fact that even with a discharged Nexus, I can still use the mount just fine, it's not that the night will be ruined. I started my astronomy journey many years ago with a fairly common setup, a manual 8-inch dob. Using the AZ100 is a lot more pleasurable because of mechanical precision and not having to deal with the stiction of a dob's teflon pads and the imprecision of the alignment. Nexus + SkySafari on a tablet is just perfect: besides the "goto" directions I like that I can move the scope manually wherever I want and see on the tablet instantly where it points. It makes it easy to point the scope to a desired area of the sky. The position was being updated in SkySafari without a discernable lag. I love atlases and have a few but confess that in the field I prefer the tablet, so I can set flipping and FOV to match my eyepiece and zoom it to fill the tablet's screen. I do my planning in SkyTools, save the observing list in Dropbox and from there I load it in SkySafari on the tablet, so it's painless. That said, I like the fact that the model is in Nexus and not in SkySafari. I can turn off the tablet or not having to rely on it without limiting my sessions. Pointing was dead on or very slightly off, which I think it's mainly due to the imprecision of alignment. I have a double-reticle eyepiece for alignment but like all perhaps, it has some parallax. I plan to give local sync a try in the future. The reason I'm posting this is that what I felt was sheer joy. Both the hardware and the software worked and faded in the background, leaving me to think about the targets. It felt like arriving, after a long journey.

To add my experience: on a Planet tripod, my TSA-120 refractor does not need a counterweight, the setup is rock solid. Rowan's support confirmed that the counterweight is not needed by the mount itself; it's only to prevent the tripod from toppling over, so they were recommending them if using the lighter Uni tripod. Other than that, the mount is superb and works very well with Nexus DSC (which I've used both standalone and connected to SkySafari on a tablet). I have the encoders as well and will get the motors when they come, but I'm very happy as it is as well, apart from charging the Nexus, I don't need any power source so it's great for multi-day outings. Razvan