Changes
/* Instrument Description */
The "Instrument Selector" is essentially a new fold mirror that has been installed in the acquisition boxes of both SpUpNIC and HiPPO<ref>''22 Feb 2024: the implementation of the fold mirror in HiPPo's acquisition box has not been completed at time of writing</ref> that allows the observer to switch between two instruments: a "primary" and a "secondary" instrument where the primary instrument is either SpUpNIC or HiPPo and the secondary instrument is always a new SHOC system. In other words, a SHOC is from now on permanently available on the 74-inch.
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 2 below that indicates the 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.