Guider Commands in Alphabetical Order

Guider Documentation

Command Description 
F6 Guider hot key. Increase delta-focus value by one step. This value starts at 1.0 mm and can be changed to 0.1, 0.3, 0.5, 1.0, 3.0, 5.0, or 10.0 mm. When the value is changed, the new value is flashed in the lower right of the screen.
SHIFT-F6 Guider hot key. Decrease delta-focus value by one step. This value starts at 1.0 mm and can be changed to 0.1, 0.3, 0.5, 1.0, 3.0, 5.0, or 10.0 mm. When the value is changed, the new value is flashed in the lower right of the screen.
CRTL-F6 Guider hot key. Flash the current value of delta-focus in the lower right of the screen.
F7  Guider hot key. Move focus of guider one delta-focus unit in the positive direction (see F6).
SHIFT-F7  Guider hot key. Move focus of guider one delta-focus unit in the negative direction (see F6).
F11 Guider hot key. Currently a no-op. May eventually increase camera integration time.
SHIFT-F11 Guider hot key. Currently a no-op. May eventually decrease camera integratio time..
F12 Guider hot key. Currently a no-op. May eventually increase camera gain..
SHIFT-F12 Guider hot key. Currently a no-op. May eventually decrease camera gain.
GAF Guider Alternate Focus. Only available at the Perkins. Toggle the position of the alternate mirror port from active (telescope beam comes out the side port) to stowed (telescope beam comes through normally). It takes about 15-20 seconds to move the mirror from one position to another. If MOVE is run in video mode (V) or no guider mode (N), MOVE checks if the guider interface is connected (in guider mode (G), the interface must, of course, be connected). If it finds it, then this command can be executed. If the guider is turned off or is not connected to the PC, then the display screen will show that the alternate mirror is "unavailable" and GAF will generate an error message. If the guider is connected, the display screen will show the current state of the mirror ("active" or "stow").
GAS Guider Alternate focus Status. Only available at the Perkins. Shows the current status of the alternate focus mirror (stowed, active, unavailble, moving, or undefined).
GBX Guider BoX. Put a guide box on the screen. The box may be moved left, right, or diagonally by one step by the keypad keys (except 5). Use - to decrease the step size and + to increase the step size. Use G to make the box size grow S to make it shrink, R to restore it to its default size. The step size, box size, box location, and central pixel value are displayed both on the image and on the screen. F1 gives help, If the GBX was called indirectly by a guiding request (either via a GLK command or from GGS), F2 will exit GBX and begin guiding; if the GBX was called directly from command mode (via the GBX command), F2 will return to command mode. F4 may be used to automatically find the star and move the box to it. If there is a valid GOS, F5 can also be used to find the star and then move the stage to put the box on the star (the position of the box will stay the same). Finally, typing HOME will enter the GXY command so that the star can be moved in the CCD frame using the numeric keypad keys. On the first call to GBX, the box size is set to 21 x 21 pixels at the Perkins Telescope and 27 x 27 pixels at the Hall Telescope and is placed at the center of the screen (at pixel location 256,256). On exit of the GBX command, the current box center and size are saved and are used as the starting value on the next call to GBX.
A number of special commands for doing encoder astrometry are available, but only via a direct call to GBX and are not available in Video guiding mode. They are ignored when GBX is called from another routine.
  • U Works much like the MOVE UC command, except that the guder box coordinate is updated to the last position on the previous move stack. Since the telescope coordinate is a fixed position relative to the box, it is also updated. Note that, unlike UC, there is not feedback and the change is performed immediately following the typed U command
  • V Same as the U command except that the telescope coordinate is not changed. The difference is absorbed as a change in the offsets (see GSO) and hence in the physcial location of home.
  • D Measure the position of the object currently in the guide box. The program coadds N frames for each measure and will repeat the process M times. The parameters N and M are requested by the program. The individual measures and their average are reported.
  • S Stop the stages if they are moving.
GCO Guider move stage by COordinate. Move the guider head to a specific RA/DEC. This command will not be accepted if there are no orientation and scale parameters currently defined.
GDB Guider DeBug. Allows moving the stages as in the GXY command, but without mapping to the sky. That is, the motions are cardinal in the guider XY stage. The guide box is displayed during the GDB. 
GDF Guider DeFault. At the 42" only, set the guider orientation and scale parameters to their default values. 
GDO Guider Dither Offset. Exclude from guide star selection, a region around the edge of the guider. This provides a dither margin for OSIRIS. 
GEG Guider Extended GOS. Does a more accurate GOS but requires that a GOS be done first. The routine places a star at each of the four corners and the center of the guider CCD in order to determine an improved scale and orientation of the chip X/Y coordinate vs N/E on the sky. It then moves the same star to each corner of the guider field in order to determine an improved scale and orientation of the guider X/Y stage vs N/E on the sky. The procedure may be interrupted at any time by typing ESC. 
GFO Guider FOcus. Focus the guider using the keypad. Use the 8 key to move the CCD away from the pickoff mirror by one step; use the 2 key to move the CCD towards the pickoff mirror by one step; use the keypad + key to increase the step size and the - key to decrease the step size (step size runs from 0.1 mm to 10.0 mm and is shown on the screen). F1 gives help. F2 to exit when done. The range on the focus is about +/-50 mm at the 72" and +/-40 mm at the 42".
GFS Guider Find inital Star. This command is used to find a star to do the initialization at the 42". It is described in detail in the guider document.
GFW Guider Filter Wheel. GFW allows selection of a filter (1 thru 10) from the automatic filter wheel. If MOVE is run in video mode (V) or no guider mode mode (N) , MOVE checks for the existence of the guider interface (in guider mode (G), the interface must, of course, be connected). If it finds it, then this command can be executed. If the guider is turned off or is not connected to the PC, then the display screen will show that the filter wheel is "unavailable" and GFW will generate an error message. If the guider is connected, the display screen will show the current position of the filter wheel. A filter designation of zero may be used to re-initialize the filter wheel.
GGA Guider GAin. Set camera gain. As of now, this command is a no-op.
GGG GuiderGrabberGain. Set gain of frame grabber. A value from 0.67 to 1.33 may be entered. The value on startup is 1.09. The current value is displayed in the guider screen. In most cases, this command will not be used by the average user.
GGI Guider move current Guider location to the Instrument. Move the telescope such that the RA/DEC of the guider box becomes the RA/DEC of the instrument (ie the telescope). As a result, an object in the guide box is moved to the instrument.
GGO GuiderGrabberOffset. Set offset of frame grabber. A value of -854 to +266 (milli-volts) may be entered. The value on startup is 50 mv. The current value is displayed in the guider screen. In most cases, this command will not be used by the average user.
GGS Guider find Guide Stars. Select guide stars. The on-line catalog is searched for stars in the guider field of view. Those found are sorted into increasing magnitude order, and presented, five at a time to the user. Stars which are inside the hole at the 42" or inside the instrument field at the 72" are excluded. If the telescope is currently locked on a track rate, a time, in seconds, is given for each star. This is the time that the guider can stay locked on that star before the head would have to stop moving due to the walls or to the instrument field. In sidereal lock this field is shown as N/A. The distance (in arcsec) between the current position of the guide head and each star in the list as well as the distance (in arcsec) between the current position of the guide head and the home position.
At any time, the user can give a star number and the stage will move to that star, or the user can enter a zero (or CR) to begin guiding on the current object. Also, one may ask for the next five stars (-3), exit GGS (-2), or one may bring up the guider screen (-1) and/or adjust the guider camera at any time using the hot keys. 
GHO Guider HOme. Move the guider head to the current home position at (0,0). ESC may be used to abort the move.
GIF GuiderInstrument Field size. Input the instrument field size radius in arc-minutes. If the pickoff mirror enters the region defined by the instrument field size, a warning is flashed on the screen.
GIG Guider move current Instrument location to the Guider. Move the telescope such that the RA/DEC of the instrument (ie the current telescope position) becomes the RA/DEC of the guider. As a result, the object in the instrument is moved into the guider box.
GIN Guider axes INitialization. Does the same initialization as on startup if the guider position file is missing. Initializes stage X,Y positons and focus (Z) positions. On completion, the XY stage is left in the stow position, the focus (Z) axis is left at zero.
GLD Guider LoaD image. Load a previously saved image into the guider screen. The image stays on the screen until a carriage return is entered. As with GSV, the default device is F:.
GLK Guider LocK. Begin guiding. The guiding is assumed to be fixed if the telesope is currently in sidereal lock and with stage motion if the telescope is currently in track rate lock. While guiding, the telescope coordinate lock is turned off (the message on the screen is given as "Off - Guiding") since guiding is now actively done by locking to the guide star. If guiding is paused (F1 toggles a pause), the program automatically resumes the coordinate lock mode which was enabled when guiding was started. In track lock mode, both the telescope and the stage will continue to move (or the telescope and the box if video guiding). Thus, the star should remain in the (invisible) box and, when guiding is resumed should still be centered in the box. However, just to be certain, the user is asked to use the paddle to move the star back into the box when exiting a pause.. Guiding is exited via the F2 key, F3 toggles a statatistics mode, F4 is a sky chop, and F5 toggles the operation of the keypad + and - keys between changing the update rate, or the drag step size.
GOS Guider Orientation and Scale.Set the orienation and scale for the guider. The user is asked to place a star in the southeast corner of the frame and press carriage return. The program automatically finds the star in the frame, and centroids on it. It then moves the telescope to the west, waits for the image to stabilize, finds the star again and re-centroids. It then moves the star 30 arc-seconds to the south, waits, finds the star, and re-centroids again. If the guiding mode is video only, this completes the GOS. The scale and orientation of the camera are calculated from these three positions and displayed in the guider screen. If the Lowell guider is being used, the stages are then moved in X, the star is found and centroided. Then the stages are moved in Y, the star is again found and centroided. The stages are returned to their initial position, the star is located again and centroided. Finally the telescope is moved so that the star ends up in the center of the field. The procedure may be interrupted at any time by typing ESC. Upon completion, the user is asked if they want to zero the offsets. If they answer Y, a GZO is performed.
GSI Guider Select Integration time. Use this command to enter an integration time which is the same as that set by the knob on the camera.
GSL Guider Select Lookup table. Choose a lookup table for the frame grabber. One of eight pre-set tables may be selected. In most cases, this command will not be used by the average user.
GSN Guider Scan. Move the guider camera in spiral search pattern.
GSO Guider Set Offsets. Move the stages as in GXY. On exit (F2), the net motion offset of the stage is added to the existing offsets. The guider box is displayed during the GSO..
GSP Guider Show Parameters. Display the current GSO offsets. If a GOS/GEG has been performed, the scales and rotations are also given.
GST Guider STow. Move the guider head to the stow position in the corner of the guider. ESC may be used to abort the move.
GSV Guider SaVe image. Save the current image on the guider screen in a FITS file. If no device is specified, the program defaults to drive F: which is on the Sun workstation. The resulting file is written in FITS and may be examined using IRAF.
GSW Guider Stow Warning. This is a toggle. Wnen it is on, a red flashing message appears in the "Stow" area of the guider screen whenever both guider stage axes are not in the stow position. If it is off (which it is on startup of MOVE), then nothing appears in this window if both stage axes are not in the stow position. 
GTP Guider Test Pattern. Load a test pattern into the guider screen. The image stays on the screen until a carriage return is entered.
GXY Guider move stages in XY.Use the keypad to move the guider X,Y stages manually. All of the keypad number keys (except 5) can be used to move the stages up, down, or diagonally by one step. The step size is adjusted by the keypad + and - keys and is shown on the screen in pixels and arcseconds. F1 gives help and F2 exits. The guider box is displayed during a GXY. GXY and GSO are the only commands which require the GOS parameters, but which will execute even if there are no parameters present (in the rare case where a guider parameter file was not found). If a GOS has not been performed, the GXY and GSO commands will use "nominal" parameters for that telescope which may not be correct. If the GOS parameters are correct, then the star will move "sensibly" on the screen. That is, the left arrow will cause the star to move left on the screen; the up arrow will cause the star to move up; etc. The current position of the guider is shown in the guider screen in microns in X and Y relative to the home position (and in RA/DEC if a scale and rotation are defined). The stages have soft limits and a warning message will appear if an attempt is made to move the stages too close to the walls. On the first call to GXY, the step size is set to 100 pixels. On each exit, the step size is saved and used as the starting step size the next time GXY is called. The guide box is displayed during the GXY.
GZO Guider Zero Offsets. Set the GSO offsets to zero.

 

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