This thread is to share information and experience regarding the Explore Scientific Exos Nano, which is a small, inexpensive equatorial mount.
It comes with several of the ES First Light telescopes, and is sold separately for $99.
I've never had an equatorial mount before, being wary of possible issues at my latitude (3°N), like counterweights hitting legs or no sight of polaris, but to satisfy my equatorial curiosity, I found the inexpensive Exos Nano worth a shot.
ES rates it for 15 lb loads, which seems optimistic for the tripod's rather thin 1.25" steel legs, so I mounted a few small scopes on it, to find out what the mount can and can't do.
Here's the entire scoop:
The box it comes in is rather small (beer and Plössl for scale):
The shipping weight was 15 lb. You can see a sort of unboxing in the video ES made for the AR102EQ3.
Here are the mount's component outside of the box:
If you watched the video, you'll notice something different here, and this is where I made a mistake, of not reading the specifications: the counterweight that comes with the AR102-EQ3 weighs 4 pounds and is thick, but the $99 Exos Nano comes with a smaller 1kg counterweight. It's clearly stated in the specs, and I should have read it instead of assuming it'd be the same.
During unboxing of the tripod, this disc was loose in the box, and after noticing that small hole that aligns well with a tiny hole in the tripod, I searched the box for a small screw that would fit, and found it. The screw never really tightens, but it does keep the black "washer" in place.
Besides from that, assembling the mount was pretty easy, and the whole thing weighs just 5.8kg (13 lbs). I added a few grams by placing a big bubble level on the tray.
Now let's mount the first scope on it: the OTA of my Orion autotracker, a 1.3 kg (2.7 lb) 80mm achromat also sold as the Orion Go Scope:
It's a feather weight scope, and in the picture it's fully balanced, clutches unlocked. If the position seems weird to you, it could be because I set up the mount for 3°N.
Notice the position of the counterweight, this is where it has to be for balance, and it easily clears the legs, so no problems at my 3°N. Movements seem smooth, but I'll have to wait for an actual first light before I can comment any further.
Now, for a different scope, a C90 (weighting 5lb) in perfect balance, clutches loose:
They seem like a good fit. The C90 will probably benefit from the slow motion controls for planetary and lunar. For even easier tracking, this mount could be fitted with the Celestron Astromaster single axis motor drive (see this thread) and I'm very tempted to try that.
For a little beefier scope, I've mounted a Zhumell Z114 OTA, weighting 2.7 kg (6 lb) including the rings+bar. Here the counterweight is no longer sufficient, and to achieve balance I had to add 1 lb of magnetic counterweights that I use with my dobsonian (got them from scopestuff):
The Z114 is the kind of scope that should work well on this mount, and it's a shame that the included counterweight is 1 lb short of working with it. I will try it on the field with the magnetic counterweights and I'll eventually post my experience here.
Finally, to test the limits of this mount, here it is holding a C6 that weighs 3.5 kg (8 lb), right about half of the alleged 15 lb the mount is rated for according to ES. In this mount, the C6 looks big, although it's not really as heavy as it looks (It weighs the same as a 5" Maksutov)
As you can see, it took even more extra counterweight than the Z114 to reach proper balance. I think it would be properly balanced with the 2 kg counterweight that comes with the Exos Nano on the AR102 F10 long refractor. That long tube must pack quite a bit of moment-arm, probably not a good fit for the mount, but the C6 being a short tube might work a little better. The mount is also sold with a 100mms Mak (I wonder how much it weighs). When the clouds cooperate and I get to try the C6 on it, I'll post my impressions here.
And that's it for now. Meanwhile I'll try to find a better counterweight. The bar is 14mms wide, in case you have any suggestions: