I started astrophotography and got the iOptron StarGuider Pro a couple of months ago. I have noticed regular tracking errors in my photos. Recently, I started auto-guiding with PHD2. The tracking graph confirms my observation.
Even with good balancing and polar alignment, I got huge track error spikes in about every 9 minutes. This happens regularly regardless of the payloads on the mount. PHD2 even complaint that the mount won't respond to adjustment during the error spikes. Is this normal? How can I fix this issue? Did I get a defective unit?
Please advise. Thank you!