During our service, when the priest is talking (homilie) I would like to have our screens black. there is a nice function on the computer for it, however during most of our services there is no one near the computer, but a member of the service (readers or singers) manage the presentation with a tablet (remotely). we haven't been able to find that function (or work around) at the remote.

I'll appreciate instructions or ideas to work around it.

Thanks