Thanks Anders! That is clear to me now. Another related question is: Which time clock is used for the timestamps? It seems to me that it is related to the time since start of my windows7 machine (Environment.TickCount) Is that correct?
Can you also tell me what the latency is between the real beginning of a fixation and the time the first event for that fixation is fired? In other words how many time does the system take to figure out that a new fixation is started? Is the e.Timestamp property corrected for this latency?