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'Alopeke Guiding Options

'Alopeke uses the Gemini peripheral wavefront sensor PWFS2 for guiding. PWFS2 operates at optical wavelengths and can guide on stars as close as 4' and as far as 7' from the science target. Guide star selection is done automatically by the Observing Tool, although it is recommended that users verify the guide stars, rejecting extended object and spurious catalog entries.