Hi. I have a problem to understand the following situation regarding observation of a quantum system: Imagine we have an unstable particle in a box, together with many sensors where each is connected to a lamp. The sensors continuously monitor the particle, the lamp turns on whenever the particle decays. Case 1: The particle, all sensors and lamps are inside the box which is ideally isolated from the universe. Case 2: The lamp of one of the sensors is taken out of the box, whereas the sensor is still inside and both are still connected. Other sensors and lamps are still inside of the box. The lamp will be monitored with a camera that takes a picture of the lamp every 5 minutes. We set up the experiment for the night. Next day, we have a large collection of pictures and we can determine the exact time of decay with the precision of +/- 5 minutes. What is the observation time in both cases? How can I relate this to the quantum zeno effect? many thanks.