Echellette Spectrograph and Imager
(Most images can be clicked on to view a larger version)
The ESI will be a Cassegrain instrument on Keck-II, which has an Alt-Az
mounting and requires field rotation to keep the object(s) in a fixed
position while the telescope tracks. The following are pictures of a
Cassegrain rotator which came from Keck-I and will be modified to
accomodate ESI, and allow it to be mounted at Cassegrain of Keck-II.
This is the condition of the ESI rotator when we first received it from
Keck
