Why parking before closing matters

Closing a dome or roll-off roof while the telescope is pointing at the horizon or at an angle can damage both the tube and the structure. The correct sequence on unsafe weather is always: park the mount first, then close the roof.

If you're using automation software like ACP, Voyager, or N.I.N.A., this sequencing is typically handled for you. But if you want a lightweight, standalone solution triggered directly from a CloudWatcher or DragonFly script, the approach below works with any ASCOM-compatible mount.

Parking via ASCOM script

The CloudWatcher and DragonFly controllers can execute VBScript actions when conditions change. The following script connects to your mount via ASCOM and issues a park command:

Dim oTelescope Set oTelescope = CreateObject("POTH.Telescope") oTelescope.Connected = True oTelescope.Park WScript.Sleep(20000) oTelescope.Connected = False Set oTelescope = Nothing

Replace POTH.Telescope with the ASCOM ProgID of your own telescope driver (for example, ASCOM.Simulator.Telescope). To find it: open the ASCOM Profile Explorer (under Tools in your ASCOM installation), expand the Telescope section, and note the ProgID of your mount's driver.

How the script works

  • Creates an ASCOM object—connects to the POTH hub (or directly to your mount driver) via the Windows COM interface
  • Issues Park—sends the standard ASCOM park command; the mount moves to its configured park position
  • Waits 20 seconds—allows time for the park slew to complete before the script exits
  • Disconnects cleanly—releases the ASCOM connection so other software can use the mount driver

Adjusting the wait time

The 20-second wait (20,000 ms) may need to be longer for slow mounts or large slews. Check how long your mount takes to reach the park position from a worst-case pointing angle, and set the wait accordingly.

Using this with a full automation platform

If you're using ACP Observatory Control, Voyager, or N.I.N.A. with the safety monitor, park-on-unsafe is typically a built-in option and the above script is not needed. The script is most useful for:

  • Standalone roll-off-roof setups where no full automation platform is running
  • As a backup park action in a DragonFly safety script
  • Simple setups where the scope is the only thing that needs to react to weather