This command controls the filter wheel. The command reports back a string similar to
done filter num=13If the num=xx argument is specified in the command line, the filter is moved to position xx. The command waits for the filter to rotate, before returning.
The home keyword sends the filter back to the magnetic `home' position and returns the string `done filter hit=ff' where ff is the number of pulses off the expected value for the home.
The check causes the stage to move to the presumed position of the home switch and then reports its status. If it is not at home something bad happens.
Positions the guider stage to xy coordinates specified. The units are between 0 and 54.8 mm. The stage command always returns the present x= and y= positions. Note: since the lead screw has a pitch of 0.1 inch per turn, the returned values will not exactly equal the metric equivalents.
The `home' keyword sends the stage to the home position at x=y=0. and returns the message `done stage xhit=xx yhit=yy ` where the xx and yy values represent the number of pulses off from the expected zero point. (One pulse represents 0.0005 inch exactly).
The slew rate of the stepper can be changed by the profile command. The low, and high, represent the stepper pulses per second.
done guider row=111.82 col=109.22 sum=651 sky=5.8is returned. Where the `row' and `col' refer to the row and column of the centroid of the image. The `sum' is the total number of counts above the `sky' value. When a centroid is calculated, a bias exposure is taken (one with the same exposure time and no shutter) and this is subtracted from the data before the centroid is calculated. A new bias frame is made whenever either: the box size is changed, the exposure time changes by more than 0.1 second, or the `bias' keyword is specified. Note: The maximum guider exposure is 60.0 seconds.
The image can be confined to a smaller box by specifying the starting row, starting column, number of rows, and number of columns in the `box' flag. If not present the entire chip is used.
The thermo-electric cooler can be turned on and off by the `cool' and `nocool' keywords. Note the cooler is turned on when the computer is booted and the server starts.
The `nbytes=' keyword initiates the image transmission. See the CCD command for the format. If no exposure time was specified, then the previous image will be transmitted.
The `dark' keyword keeps the shutter closed, however, waits for the specified time before proceeding.
To display a 12 bit image on a 8 bit screen, usually the data are shifted right by 4 places. However, to increase the contrast, you can specify a smaller number. Note: the shift value is stored as a program static and will remain until it is either changed or the guider server program is restarted (at which time it goes back to 4).
Last Revised June 1, 2001