User's Guide to the Kast Double Spectrograph


Table of Contents


Introduction
Quick Reference
Hardware Overview
Common Path
Blue Side
Red Side
Detector Characteristics
Software
Kast Controller
Data Taking System
Position Angle
Arc and Flat-field Lamps
Diagonal Mirror
Kast Focus
Eventsounds
Setup and Observing Hints
Setup Procedures
Observing Hints
Calibration Lamp Spectra

Mt. Hamilton Homepage

Kast Controller

The user interface for the Kast motor controller is started from user account on shanepc by typing kast. You will be presented with a menu like that in Figure 1. The controller will display the current spectrograph setup, and will allow you either to change the individual parameters, or to reconfigure using stored setups.

The spectrograph controller operates three separate motor controllers which work in parallel, an devices may be queued up for all three of them. This means that if you want to change a number of items, you should not wait until one is done before requesting the next change. Make as many changes as you wish as quickly as you wish, and the controller will get it all done as soon as possible. The display will inform you what the status is of each item; queued, moving, or move completed.

The controller comes up in the immediate change mode (Figure 1). In this mode, you select an item by typing in the letter on the screen which corresponds to the item you wish to change. You will then be prompted to enter a code for the change you wish to make. The code might be an ordinal number corresponding to a filter position, for example, or it might be a precise position in terms of stepping motor steps, or it might be a name which corresponds to the contents of the position you desire.

Entering a number alone, such as xx, will set that item to an ordinal position. A decimal point after a number, as xx., will cause a move to a specific stepping motor step. Adding two exclamations points to an entry, like xx!!, will cause that item to reset during the move. To make incremental moves in stepping motor steps, add an explicit sign, e.g., +xx.

Named entries are probably most convenient just because they're easier to remember. For items which are not user changeable, see the tables in this manual for the names of various positions.

For user changeable items (user filter wheel, dichroic carriers, and gratings) you may name them anything you wish. This is done with the Z-1 option (type Z and get a submenu, then type 1 to select the configuration option). For example, if you wish to change the name of user filter wheel position number 3, type F to select the user filter wheel, then 3 for position 3. You will be prompted for a position number (in this case it's a redundant 3, but in some non-user naming it's not a redundant question - sorry), and then for a name. Usually it makes sense to give sensible names, like h-alpha, but there's nothing to stop you from naming it Dr. Spock if you wish. When you have the names assigned as you want them, type escape to get back to the calling screen.

Figure 1: Kast Controller User Interface, Immediate Mode

During your initial setup of the instrument, it's usually most convenient to operate in the immediate mode. Saved setups are usually recorded after you have the instrument pretty much tweaked up, for quick recall later in the night or the next day.

In the setup mode, you may use any of 20 setups (see Figure 2). To selecte the setup mode, type S. Then you will be asked to select a setup number between 1 and 20. The setup you selected will be displayed (if it's your first night, it'll probably be a left over setup from some prior observer). Then you can operate on the setup list, rather than directly on the spectrograph. This is convenient if you wish to modify the request list and save it to disk without actually changing the spectrograph, for example. To go back to the direct mode, type S for setups, then 0; this will save all setups and remove the setup list from the screen.

If you are working with a setup list, numbers entered change the list but not the spectrograph. You must type R to actually change the spectrograph setup. It is very important to fix in your mind that recalling a setup does not change the spectrograph. More than one tired astronomer has recalled the setup but forgotten to set the spectrograph, with the unfortunate result of observing with the wrong setup.

If you are working with a setup, but nevertheless wish to force and immediate spectrograph change, add an exclamation to the entry, e.g., xx!. Entering * in the setup list will cause that item to be ignored (including the reinitialize command).

You may change the naming conventions which the program expects from submenu Z-2 ("options"). Type A, and you will be given three choices for naming positions: Match Setup (1), Physical (2), and Name/Ordinal/Physical (3). Choose the option you want by number. "Match Setup" means that the program will accept whatever naming convention you have adopted for that item in your setup. "physical" means it will accept only stepping motor step numbers. "Name/Ordinal/Physical" means you can enter any of those three types of names and it will try to figure out what you want.

Ctrl-C aborts moves, Ctrl-Y exits.

Figure 2: Kast Controller User Interface, Setup Mode