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Title: An optical distortion solution for the Keck I OSIRIS Imager
We calculate an optical distortion solution for the OSIRIS Imager on the Keck I telescope, by matching observations of globular clusters to a Hubble reference catalogue. This solution can be applied to correct astrometric distortions in OSIRIS frames, improving the astrometric accuracy of observations. We model the distortion with a 5th order Legendre polynomial. The distortion we find matches the expected OSIRIS distortion, and has a fit error of 0.6 mas, but has large residuals of 7 mas. We are currently iterating on an improved reference frame to improve the residual. Additionally, we have installed the Precision Calibration Unit (PCU) on the Keck I optical bench, which will generates an artificial grid of stars for use in future distortion calculations.  more » « less
Award ID(s):
2108185
PAR ID:
10356648
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Editor(s):
Schmidt, Dirk; Schreiber, Laura; Vernet, Elise
Date Published:
Journal Name:
Adaptive Optics Systems VIII
Volume:
12185
Page Range / eLocation ID:
121853R
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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