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Old 28-06-2025, 03:52 PM
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Pierre_C
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Join Date: Aug 2024
Location: Melbourne, Australia
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Quote:
Originally Posted by bojan View Post
...something is moving there.
Quote:
Originally Posted by Ramius View Post
Yes the really obvious aberration disappears near the zenith.
Random thoughts:
  • Gravity dependent movement of the primary mirror or primary mirror housing - could there be lateral movement of the mirror, apart from vertical movement from loose clips?
  • Gravity dependent movement of the secondary mirror? Check tension of secondary mirror and spider vane system?
  • Flexure in the optical tube affecting the relationship betweeen the primary mirror and the secondary mirror?
  • Gravity dependent movement in the focusser or imaging train?
Check collimation at the zenith and then in each cardinal direction after adjusting each component to see if there is any difference?
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