Why is my Polar Alignment not repeatable?

Owned by Pieter Smith (Unlicensed)
Last updated: Jun 09, 2020
1 min read

Problem

Repeating the Polar Alignment procedure gives a different result every time

Cause

Polar Alignment, as with any measurement process, is subject to an inherent measurement error. When repeating Polar Alignment, you can therefore expect a slightly different result every time. How wide-ranging the results are, is a function of how smoothly your mount tracks, the seeing and the length of the measurement.

Solution

Longer measurements improves accuracy, making it less sensitive to tracking errors and seeing. So follow these steps to pick a measurement time that gives you good results for your mount without wasting time:

  1. Perform a Polar Alignment with the Precise (10 min) measurement. The 10 min measurement is long enough to compensate for the periodic tracking error on all tested mounts.

  2. Repeat Polar Alignment a few times with the Standard (2 min) measurement. Record the measured alignment error every time. If the alignment error is acceptable, you can safely use the Standard (2 min) measurement for future alignments with this mount.

  3. Repeat Polar Alignment a few times with the Quick (30 s) measurement. Record the measured alignment error every time. If the alignment error is acceptable, you can safely use the Quick (30 s) measurement for future alignments with this mount.