To select between the primary instrument and SHOC, a user can actuate the fold mirror in/out of the beam to direct the science beam towards the desired instrument (see figure below for button on TCS that actuates the fold mirror). When the fold mirror is IN beam and the guider's XY stages are "centred" then the guider camera also functions as a "target acquisition" camera for SpUpNIC/HiPPo, similar to the old system. Also as in the old system, the guider can patrol the area of the large annulas mirror to acquire an appropriate guide star.
== Important Notes ==
NB. (1) Because the fold mirror and annulas guide mirror are displaced relative to one another in the optical z-axis the guide/acquisition camera's focus has to be adjusted substantially when switching between guiding and target-acquiring mode. This cheat-sheet provides guidelines for focus settings and summarises instructions how to set up target-acquisition and guiding for the primary and secondary instrument: [https://docs.google.com/document/d/1lcwk0bJi393BTLG7yscAMS0l4lCA6JHsOp3g3hbeSOg/edit?usp=sharing cheat-sheet].