4 replies to this topic

[TicoWiko]

I'm the recent owner of an AM5N. While I will eventually start using it for AP, it's first purpose will be as a portable visual rig. My only major issue on that front is the accuracy of the goto system. I've read conflicting reports on how well the multi-star align is supposed to work, and was wondering if anyone here had managed to make it work reliably well. The tracking is excellent, easily holding a planet centered in even a very high power FOV for a very long time, but I've found the goto to just be completely off... Even slewing back and forth between Pollux and Castor, after having synced to both, only works on occasion. Anything further and I'm always off by multiple degrees. Has anyone managed to make it work reasonably well ? I'm not asking for arcminute accuracy, but I'm multiple degrees off even when slewing back to a star I just synced to. Granted I've just played around with it for one night, so there may be things I'm doing wrong. Here are 2 things that maybe I can improve :

 

- Better leveling : the new version of the mount doesn't have an integrated bubble level, so I use the Bubble Level app on my phone by setting it flat on top of the mount. Given the digital indicators this is probably more precise than a visual bubble level. I had it near perfect on my second run, but this didn't seem to help much. But I did notice that after a few hours of use the mount was suddenly much more tilted than it was initially... Could my setup be shifting around somehow ? This might be related to my second point... Or maybe I need to setup over more solid ground, like concrete instead of grass.

- A more stable tripod : I'm using the stock ZWO tripod. I realize it's not the most stable tripod around, but I figured that mattered more for AP and I got it as a lightweight, compact, grab and go tripod for ease of use and transport. But is it possible that it's so light and/or unstable that the mount is slightly shifting it as it slews around ?

 

Really hoping to get this to work better, because the mount is ticking every other box I need as the base of my travel setup : compact, simple interface, easy and reliable bluetooth connectivity, wonderful hand controller, great tracking etc. If I could just get this thing to point itself a bit better it'd be absolutely perfect. But as it stands my dob with a degree circle and an altimeter does a faster and much more reliable job of finding things. Honestly even if it were only reliable in the neighborhood of the last synced star that would be fine, as I could just sync to a nearby bright star then hop to my DSO. But even that has not been particularly reliable...

 

Very open to feedback on how I could improve this, or even just being told that unfortunately the AM5 just does a very poor job of this no matter what. If the latter then maybe I'll start working on how to put a degree circle on the AM5...

[mayhem13]

Stability is everything. You’ll find the AP crowd using the AM5 with the CF tripod are plate solving which goes beyond basic GOTO functionality. For visual, you can still use plate solving with a guide scope for visual. I’d suggest this route as eventually you will be doing AP so get familiar with guide scope routines now. You don’t need an off axis scope at the moment…..a cheap 60mm stand alone scope will do just fine for plate solving. Buy the camera you intend to use for guiding off axis later as to avoid redundancy.

 

A leveled mount is pretty much meaningless after polar alignment has been performed and the system is stable. If you can set your tripod on solid surface like concrete, much better. If not, ballast weight hanging from the tripod helps. Most folks are using this mount as a grab and go for short widefield focal length which are much more forgiving than say 1500mm. Lol

[TicoWiko]

Stability is everything. You’ll find the AP crowd using the AM5 with the CF tripod are plate solving which goes beyond basic GOTO functionality. For visual, you can still use plate solving with a guide scope for visual. I’d suggest this route as eventually you will be doing AP so get familiar with guide scope routines now. You don’t need an off axis scope at the moment…..a cheap 60mm stand alone scope will do just fine for plate solving. Buy the camera you intend to use for guiding off axis later as to avoid redundancy.

 

A leveled mount is pretty much meaningless after polar alignment has been performed and the system is stable. If you can set your tripod on solid surface like concrete, much better. If not, ballast weight hanging from the tripod helps. Most folks are using this mount as a grab and go for short widefield focal length which are much more forgiving than say 1500mm. Lol

I'm aware of how much more accurate I can make things with the added investments you mention, and indeed as you said I'll be making many of them eventually for AP. But even then, I'd be interested in improving accuracy as is for simple casual observations. My current setup fits entirely in a single padded case containing both the AM5 and my EPs. I can lift that + the tripod + my scope case all in one go and be observing in 10 minutes. I really don't want to throw in cameras, guide scopes, plate solving etc. for casual visual when on vacation or during outreach, or even just for a quick observing session at home. Honestly apart from this one issue this setup is fantastic : very compact, fairly light, simple and very reliable tracking, and again the hand controller is loads of fun. It would be absolutely perfect if the gotos were juste vaguely accurate.

 

And I agree a long FL is less forgiving, but that's really not my issue here : half my slews are so off they're not even within my widest Telrad circle.

 

And one last point : I'm doing visual in AZ mode. Quicker setup, easier observing, and more intuitive manual controls. Would EQ mode be more precise ?

 

I'll try again tonight on concrete. Maybe that's more of an issue than I imagined it to be...

 

Thanks again for the feedback !

 

Clear skies

[scanner97]

I've read about isses with goto accuracy (with HC + app only) but they were a couple years old.  Have you tried posting in the AM5 thread?

 

I didn't see what scope you're using.  With something like a C11 or a large/long refractor, the stock tripod is probably not what I'd recommend.  With a 4" or smaller frac, it's perfectly fine - even for AP.  (Folks are doing AP on it with a 5".)

 

Good luck!

[TicoWiko]

I've read about isses with goto accuracy (with HC + app only) but they were a couple years old.  Have you tried posting in the AM5 thread?

 

I didn't see what scope you're using.  With something like a C11 or a large/long refractor, the stock tripod is probably not what I'd recommend.  With a 4" or smaller frac, it's perfectly fine - even for AP.  (Folks are doing AP on it with a 5".)

 

Good luck!

I'm using a C9.25. Not at all looking for AP level precision here, just a reliable visual experience. Will try the thread, thanks !