Recently started experiencing issues with the AM5N, and I'm having trouble nailing down what's happening. I've been running this mount since January, and guiding has been relatively good but over the last few weeks I've been seeing star trails due to an RA correction that is creating trails on 50%+ of my subs.
I started with the default settings on the ASIAIR+, and just changed the exposure settings from 2s to 1s or 0.5s to try and improve guiding. I recently tried with a different guide camera, but the issue still persists leading me to think it's something else.
Everything has been tightened down on the scope and the mount, there is nothing flexing at all. I have placed the tripod (TC-40) on some heavy cinder blocks to stabilize and that has helped significantly when I am tracking on the east side of the pier. Whenever the pier is on the west side, we get these spikes.
Equipment Details:
- AM5N
- ASIAIR+
- ASI2600MC Pro
- RedCat 71
- ZWO EAF
- WO 32 Uniguide 120mm
- ASI120MM Mini
- ASI715MC (new camera, tried to use this to see if there would be any improvement.
Attached my guiding logs from a good session (2025-03-08 and 2025-03-12), and then from 2 sessions where it just got terrible (2025-03-14 and 2025-03-25)
Link to guiding logs
- Polar alignment under 1" using the AA routine, did this twice to ensure it didn't change.
- Performed a guiding calibration as close as I could to the meridian and celestial equator, although this is pretty far in DEC (+37.1) since there are a lot of trees on the south side of the telescope.
- First target was North + East of the meridian. Within the first 10 minutes, I got the -45" peak on the RA. I have a short video while I was watching the guiding session here. I switched targets and continued guiding, started getting the RA peaks after 15-20 minutes in (max -28.86" peak), video here.
- I then switched sides and pointed to a target North + West of the meridian, over an hour of guiding with no RA peaks over 5". Total RMS was 0.97".
- After I turned off dithering 2 nights ago, I didn't turn it on to ensure this wasn't causing any adverse effects.
Calibration ran automatically for my Plan, but guiding ran pretty horribly with the max peak around -53.62". I noticed in the graphs that it took about 20 minutes for the first peak to happen and then it just continues with those peaks 5 minutes. Although, eventually I can see during the session that I get 2-3 additional smaller peaks the longer it goes on. At 03:10 EST, it did the meridian flip and started on the East side of the pier, guided for over an hour at 0.74" RMS with no peaks.
I'm noticing that the issue seems isolated to the west side of the pier. My view from the backyard is strictly north, so my targets are within 2-3h either side of the meridian.
I've made sure the tripod is weighed down with at least 20-25lb weights. The nights I tested there was minimal wind, and no clouds at all coming through.
From the East side of the pier, the guiding is pretty good for me:
From the West side of the pier, the guiding has these very high peaks which guiding attempts to correct:
I reached out to ZWO support last week, and I still don't have a response to any of my queries.
