Command dictionary for INT high-level Telescope Control.

add adds a new entry into the observer's tcs catalogue.

aperture set telescope to given aperture number.

focus set telescope focus.

gocat Slew telescope to given catalogue entry.

guide control autoguiding.

next Slew telescope to edit-block entry.

object Enter new object into edit block.

offset offset telescope by small amount.

point log a position in pointing test.

rotate Rotate instrument rotator.

Detailed command description:

add adds a new entry into the observer's tcs catalogue.
```
> add
```
will add the object currently in the internal edit-block to the catalogue (for how it got there, see object).
```
> add name
```
saves an entry by name with the current telescope coordinates. (mark/source).
Returns non-zero status if name already exists in the catalogue.
aperture n set telescope to given aperture number.
n may be 0-5; for the Wide-Field Camera, apertures 1-4 represent the centres of the four chips, aperture 5 is the part of the autoguider chip nearest the rotator centre, and aperture 0 is the nominal aperture, in this case the centre of the science array. (In fact, since the Perkin Elmer TCS can only support nominal aperture, aperture A and aperture B, this command maps 1-4 onto aperture A)
eg:
```
> aperture 1 
```
focus x sets the telescope focus in mm.
eg:
```
> focus 19.26
```
gocat name Slew telescope to given catalogue entry.
eg:
```
> gocat M31
```
Returns non-zero status if name is not found in the catalogue.

guide Control autoguiding stop/start.

> guide [on | off] [on star  | on pixel   ]
 
> guide                     // provides usage information
> guide on                  // guide on star 1
> guide on star 3           // guide on star 3
> guide on pixel x y        // guide on pixel x,y
> guide off                 // finish guiding

See also INT-AUTO-6, User Manual for the INT Autoguider.

next Slew the telescope to the object whose coordinates have been placed in the edit block, eg by object. Use of this means of slewing the telescope is necessary to ensure valid CAT- FITS headers.
eg:
```
> next
```
Returns non-zero status if asked to slew the telescope beyond its mechanical limits.

object Enter a new object into internal edit-block.

Usage:

> object name hh mm ss.s dd mm ss.s A|Byyyy|Jyyyy [pR pD [epoch [Px [RV]]]]

 
                  name: simple string, no spaces allowed.
                    RA: int hours, int minutues, real seconds.
                   Dec: int degrees, int minutes, real seconds
               Equinox: A for apparent, B1950 for Besselian or J2000 for Julian
        Proper-motions: real seconds of time/year, real seconds arc/year
                 epoch: real year, epoch of proper motions
              parallax: seconds of arc
       radial velocity: km/s
 
        defaults>
        proper motions: 0
                 epoch: equinox
              parallax: 0
       radial velocity: 0
 
eg:
> object NGC3628 11 20 8  13 36 30 J1997.5


Returns non-zero status if insufficient parameters are given, or
values are out of range.



offset offset telescope by a small amount.

usage: > offset ra t|T|s|S dec

eg:
> offset 20 s 10 offsets by 20 arcsec in RA and 10 arcsec in DEC.




point
Logs current telescope raw-encoder coordinates into pointing log. The
task POINT.TSK must be running on the Perkin-Elmer.  This is not a common-user
command. Must be used in the sequence point BEGIN which
writes a TPOINT-compatible header file in $OBSSYS/etc/point.aux, followed by
a sequence of point name as each object is centred,
and finally point END to close the file.  Each invocation
of point name causes the Perkin Elmer to write
to POINT.DAT etc. eg:
> point 00+00 




rotate
Send instrument rotator to given angle.  The TCS `knows' which focal-station
is in use.  The two useful invocations for the INT are rotate sky 
theta and rotate vertical.  The former sends the
rotator to the give sky position angle (0 < theta < 360),
and the latter to the current
parallactic angle.
eg:
> rotate sky 180 

Returns non-zero status if demanded angle is out of range for a given
platform.



The Observer's Catalogue
The observer's catalogue is a text file in the same format as used for
the WHT.  It is stored in $OBSSYS/etc/tcs.cat.
The commands add
and gocat operate on the catalogue; all other functions, such
as delete, save-to-file, sort, etc, must be performed with normal
text-editors and shell commands.
 The following is an example of a part of a catalogue; note that comments
may be inserted if preceded by an exclamation mark!
! Version 1.1, ptgrid.cat.
 00-45 23 59 01.420 -45 37 22.45 B1950.0 -0.0013 -0.027 1961.
 00-30 23 58 33.646 -29 12 37.21 J2000.0  0.0035  0.007 1990.33 ! 8.41
 00-15  0  0 24.645 -14 29 25.71 J2000.0  0.0115  0.001 1993.57 ! 9.08
 


The Edit Block
The edit-block referred to in some of the commands is simply a static
area of memory used to hold the target information of a single source;
eg the command object causes the D-task to hold
the information for a new object internally;  then a subsequent 
add or next command may operate on that
information.



This page is tcs_command_reference.html v1.1, last revised on 97/03/17.