In
both cases a dialog box allows to select the monitor
where the desktop picture will be placed, the position
and the update rate.

iCamMaster
depends on the Appearance Control Panel found in System
8.6 or later to place pictures on the desktop.
The
picture will be updated while iCamMaster is running. If
you quit the picture will continue updating the next time
you launch iCamMaster.
To
change the settings of a desktop webcam or to remove it,
select "Desktop Cams..." in the "Edit" menu.
In
the dialog box simply select the monitor you want to
change the settings and make the modifications, press the
"Remove" button if you no longer want the webcam on the
desktop.