Automatic range calculation means that the first entries are used to compute a suitable range.
The number of entries used to set the scale is equal to half the number of bins of the histograms. You should ensure that the number of track iterations is at least equal to half the number of bins.
Keep in mind, if you do so, that the accuracy of the median arrival time of the selected electron can be reduced because the arrival time distribution is likely to cover only a small fraction of the range of the histogram.
Formatted on 21/01/18 at 16:55.