Instrument Control
The Hamilton is fully remote-controlled. When used with the 3-meter, it is operated from the Readout Room, just off the main observing floor. For CAT operation, the spectrograph is controlled from the CAT computer room in the basement of the dome.
Two programs--the Hamilton control program (hamit) and the data-taking program-- provide control of the instrument. These are briefly described below. They are described in much greater detail in the Hamilton manual, and are covered as part of a new observer's training.
Operation is nearly identical for the two telescopes, however, unlike the 3-meter, the CAT is a user-operated telescope: observers must be trained in its use, irrespective of previous experience with the Hamilton.
The user configurable parts of the spectrograph--such as slit width, grating tilt, and calibration lamps--are controlled from any of three identical terminals located in the Readout Room, the CAT computer room, or the slit room.
The Hamilton control program is organized as a menu of commands that request further input or invoke sub-menus. It is largely self-explanatory and quite easy to use. Pressing the "escape" key moves one towards the top-level menu, as well as backing one out of most difficulties.
Operation of the program is identical for the two telescopes. Bear in mind, however, that the decker and aperture plate choices are given in arcseconds at the 3-meter plate scale; CAT observers should multiply by five.
To start the program, type "hamit" from an xterminal hosted by catpc.ucolick.org or look for "hamit" on the pulldown menu of the observer's terminal.
The data taking system is run from workstations in either the Readout room or CAT control room. Slightly different versions of the data-taker apply to 3-m and CAT and to the different detectors. Start each as follows:
| 3-m ROR (shanepc) | CAT (catpc) | |
| Dewar 6 | hamx | hamcat |
| Dewar 8 | hizx | hizcat |
The data-taker creates three windows: the menu-driven "dtake" window through which the observer controls CCD and integration parameters, the image display window which displays the raw CCD image (and can redisplay stored images), and the image control window which provides interactive controls such as zooming, simple plotting, and color-table manipulation.