1.3m Pointing Reset

If the 1.3m pointing is ever inaccurate, for instance after reseting the port server, it can be corrected at zenith by using a few simple command line operations as well as some adjustments via the virtual telescope hand paddle.  

a) Verify that tracking is OFF.

b) If the telescope is not pointed to zenith already, move to zenith with the command:

point ha=0 dec=31:57:12 nodome

Unless the telescope is completely lost, this should get you to where the tilt sensor values are actively converging towards zero.  

c) With the telescope upright and the tilt sensors near zenith, there is the choice of either making finer point demands via the command line or utilizing the virtual handpaddle to zero in the tilt sensor values relative to the stated zenith values.  For the handpaddle, set it to 60 [arcseconds per demand].  Each press of a directional button will change the tilt value amount by roughly 2 units.  Issue commands until the sensor readouts roughly match the stated zenith values.  

d) Zero the coordinates with the command:

zero ra=SI:DE:RE dec=31:57:12 equinox=nnnn.nnn

where SI:DE:RE is the sidereal time roughly 10 seconds in the future and nnnn.nnn is the current equinox as displayed in the TCS.  As the local sidereal time is roughly 2 seconds away from the typed value, strike <enter> to zero the coordinates.  Telescope coordinates are now roughly aligned.

Fine Tuning the Pointing Further: this can be done even when the pointing is not entirely off.

e) Restart JSkyCalc if necessary--if the TCS GUI has been restarted, restarting JSkyCalc will be necessary to re-establish connection.

f) Turn tracking back on.

g) Select the "nearest bright star" to get the coordinates of a bright star near the zenith or your target.

h) Use "start slew" to slew to the star.

i) Center the star in your field of view by walking the star in using the virtual handpaddle.

j) In JSkyCalc, pop up the "Alt Coordinates" window to get the RA and declination of the present equinox.  Use these (do not use J2000 or ICRS coordinates!) to zero the telescope pointing with the command:

zero ra=hh:mm:ss dec=dd:mm:ss

k) Verify that the TCS shows the same coordinates as the "alt coords" window before moving on.