I chose the break beam as opposed to the PIR sensor because its straight break line makes for an easier place to focus my camera.

我选择了断光束而不是 PIR 传感器，因为它的直线断线使我的相机更容易对焦。

You can trigger the system in different ways, but one common way is by using a passive infared sensor, or a PIR sensor, which typically detects abrupt changes in heat in a coned area, then triggers the camera and flashes.

您可以通过不同的方式触发系统，但一种常见的方式是使用被动红外传感器或 PIR 传感器， 它通常会检测锥形区域中热量的突然变化， 然后触发相机并闪光。