Algorithm used in los2 function

I am using the los2() function to evaluate line-of-sight between two points. The function indicates that line-of-sight is lost when the elevation of the second point in the AER frame centered on the first point is greater than zero; point values corresponding to an elevation of zero are indicated as being below the horizon.

As far as I understand, all points at or above zero elevation at a particular location should be within line-of-sight from that location; however, this does not appear to agree with the results from los2. Is my understanding of the LOS calculation inaccurate or am I missing something about the way los2 performs its calculation?

[Epsilon]

Hi Thomas, there might be various reasons for this discrepency. Can you please share your file so that we can have a better look at it.