How to setup Neo Coolcam motion sensor to operate properly

Hi all,

I installed garden lights and 2 motion sensors in the garden at the back and in front of our house. So far so good. However, I was wondering how I can setup the Neo Coolcam motion sensors in such a way that it only reacts when it is really necessary. Currently it sees almost every movement, which will probably drain the batteries, but turns on the lights almost continuously. FYI, I already have the settings at lowest sensitivity and turned the sensors a bit downward, while they hang at about 2.6 meters.

Any suggestions to have them less sensitive but still seeing non-invited persons?