Filter Wheel Ascom Window

Newbie question here - when I ‘connected’ the filter wheel simulator an Ascom window opens and shows the filter color. However, when I connect my ASI EFW-7 no Ascom window opens. I know the driver and filters are set up properly because I can ‘Set’ the filter through the Control Panel/Filters feature. Should I expect the Ascom window to open or is that just a feature of the simulator? Thanks in advance for your help.


The short answer is “it depends on the driver”. Some will open up additional “helper” windows others will not. It really varies driver by driver. Most drivers don’t tend to open up an external dialog (the exception seems to be mounts, which almost always seem to).

If you’re looking for a way to manually control filters I’d recommend the Filterwheel Dock Module:


ASCOM specifies that a driver should not open user interface, with the exception of the setup dialog. This is because it could be running on a remote PC where the only interaction is through ASCOM. Some drivers will show a dialog but it must be additional and never need the user to interact locally. For example showing a message box is not allowed, not even if there is an error.

Simulators are a bit different, the UI they provide is really a way of providing an alternative to a hardware connection, and not all simulators do this.