The tricks of using the laser level on a sunny day on the street without a special receiver. Instead of a receiver, a mobile phone’s camera, with which the upper and lower points of the beginning of the laser beam on the phone’s screen are determined. After that, the segment is divided in half by eye and checked by the camera of the phone in the middle.
In this case, the task was to put a mark on all pillars at the same level relative to the horizon.
It does not matter where to put the risk on the mobile phone, it is important to make marks on the poles at this risk.