It is possible to set the digital output buttons to latch open so one press will activate the digital output for a set duration of time specified in the menu. This option can be adjusted on a per camera basis.
Simply select the camera you want to adjust the alarm output time for and right click on that channel and select ‘Advance Alarm DO’.
Now adjust the ‘Alarm Output Interval’ value to the amount of time you would like the DO to latch for.
Now you should be able to trigger the DO using the ON alarm button and the alarm output should stay on as set.