* If you edit the catalogue file, you'll need to reload it into the GUI before the changes will appear in the drop-down list.
===Setting up the slit position on the TCS - using the SpUpNIC Control GUI===
The purpose of this step is to figure out where on the acquisition image you need to place your star, in order for it to land close to the ideal spot on the slit. Very bright stars can be seen reflected on the slit jaws, and can be placed on the slit directly, but this is not the case for fainter stars, which need the superior reflectivity of the guide mirror in order to be seen on the acquisition camera.