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Problem: Cruciform Images
Manifestation:
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Cruciform images (typically at Hour Angles > 2.5).
Solution/Recovery:
First Level:
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Explore changing the control matrix from default to
WLS, Dim, or Zero
(depending on conditions).
Second Level:
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Return to zenith, re-align and hope the shift does not recur when
re-visiting high airmass source(s).
Cause:
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Low signal in wave front sensor.
Sometimes induced by alignment
shifts of the laser amplifier/launch telescope, resulting in power
drop/reduced signal at Hour Angles > 2.5.
Associated Issues:
Change Log:
- 2018-08-24: First version.
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