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[SOLVED] Nexstar 4SE Alignment and Sync issues

Few days back, when I was trying to do some random stellar observations, I realised that the 4SE wasn't aligning properly and the goto function was off a little more than you'd expect. Given that weather wasn't on my side, I decided to let it go for the moment. I finally made a one star alignment and was trying to get the Sync function to work (the Sync function, when activated, would track the current position it is pointed to by auto adjusting to compensate for the stellar movement). The first worrying point when the controller returned an error that said "Offset too large, Sync failed".

Yesterday, while I was trying the same, I was trying to align the telescope using the Two Star Alignment mode. After trying to align using two reasonably nearby stars (Alpha Centuri and Hadar and repeating with Alpha Centuri and Acrux), the controller was returning an error that said "Align failed". This was even more worrying.

It is only slightly later that I realised that the batteries of the telescope was running really low. The handset was lit up, but the telescope motor wasn't responding. After replacing all eight batteries, the telescope was back up properly. It was aligning properly and also syncing properly.

So what was the problem? My take on the matter is that the 4SE does not actually have a feedback system. it does not really track the motor positions, it takes the current motor position when the alignment starts and then computes where the telescope should be pointing based on the controller input. There is no other way that I can try and explain it. The motor doesnt move by much as the power is too low, and the user keeps pressing the directional buttons to move the telescope. The controller circuit actually believes that the telescope has to move by that much and cannot find matching stars. This causes an alignment and a syncing error.

I think the best Celestron should do is to provide a low battery warning on the handset. That atleast would help users to identify that they need replacement without waiting till the last moment.

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