I am writing to formally raise a serious concern regarding the performance of my recently purchased AM5N mount, which, contrary to the product’s advertised precision and reliability, is exhibiting severe, unexplained deviations on the RA axis, rendering it effectively unusable for consistent astrophotography.
Despite rigorous troubleshooting, including optimal balance, cable management, environment control, and multiple software platforms (ASIAIR+, NINA, and PHD2), I continue to experience RA guiding errors in excess of 6-8”, in stark contrast to ZWO’s advertised sub-arcsecond tracking performance.
To illustrate:
Guiding used to work well for the fist two weeks from new (0.5" RMS), but the mount now sporadically produces RA excursions of 8”+, with no environmental, setup, or hardware changes.
Troubleshooting has included:
Removing accessories to eliminate electrical or weight-related causes.
Testing various guide settings: 500ms to 100ms exposure, RA aggressiveness from 20–85%, Sideral rates from 0.75x to 0.25x.
Trying multiple power supplies and USB cables.
Using both ASIAIR+ and PHD2/NINA for guiding.
Testing with and without counterweights.
The same OTA and imaging train, when installed on my iOptron CEM40 EC, consistently delivers round stars on 300-second exposures, demonstrating the optical setup and overall environment are not the cause.
This situation raises several issues beyond mere inconvenience:
ZWO’s reputation is at stake. Your AM5/AM5N series was promoted as a revolution in harmonic mount design—simple, portable, and precise. Mounts that behave unpredictably and unpredictably deviate this drastically risk undermining the trust users place in your brand.
This is not a user error. I have adhered meticulously to best practices and thoroughly documented my process, setup, and results across platforms. This is not a matter of poor polar alignment, cable drag, or bad calibration.
Significant financial investment. The AM5N and related ZWO ecosystem represent a serious financial outlay. Users like myself, who are committed to this hobby and your ecosystem, expect professional-grade performance and support.
Negative community impact. Continued unresolved issues without transparent resolution or accountability may deter prospective buyers, especially as user forums begin to raise similar concerns without clear solutions.
I respectfully request:
1) A formal investigation and escalation of this case.
2) Direct technical feedback from your engineering team regarding the nature of this RA anomaly.
3) Clarification on whether this is a hardware fault, firmware issue, or systemic problem affecting a batch of mounts.
4) Options for mount repair, replacement, or firmware rollback if applicable.
I have attached all relevant logs, screenshots, calibration data, and guiding performance charts for your detailed review.
I urge ZWO to act in alignment with the high standards it promotes and demonstrate that customer satisfaction is more than a slogan—it is a commitment. I am more than willing to work with your team to diagnose the root cause, but a generic checklist response or delays in meaningful action will only heighten dissatisfaction.
Thank you for your time and consideration. I look forward to your swift response and a clear plan of action.
Please find attached
more logs to assist with your investigations
