NEXDOME OBSERVATORIES NEXDOME.COM
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Figure 8: Dome Setup
If this is the first time you’ve run the software, the dome will need to be calibrated too. Make
sure you are not connected to a telescope and that the track and slave boxes are not selected
(if they are, the calibration will fail). First, home the dome. When that is done, the calibrate
button will be available, press the “calibrate” button. The dome should rotate and then stop
when it reaches the switch. This data is stored in the control box and is used to compute the
number steps the drive makes to move the dome a specified number of degrees.
The last thing that is required in setup is to tell the computer where the scope is in relation to
the dome slit. This geometry is used to compute the position of the scope and slit relative to
each other.
The measurements needed are taken from the center of the dome and reflect the telescope
rotational axis (Fig 9) offset North (considered positive), South (considered negative), East
(positive), West (negative) and if the rotation point is above (up, positive) or below (down,
negative) the rotational base of the dome. You will also need to know the dome radius. Note, in
POTH, the offsets are measured in millimeters and the dome radius in meters.
