Position Comparison

Subtracting the event list images for the two files shows that there are 124 pixels for which the total number of events is different. Ninety-six of the differences are due to split events which, because to differences in the biases or processing order, have a difference in the position of one row or column.

Table 4.20 is an example of an event found in the exposure taken at 22:45.558 GMT (frame 502 for the High Speed Tap, frame 5075 for the telemetry). Due to the 3 ADU difference in the bias levels, the peak of this split event was found at two different positions.

 

r/c Telemetry High Speed Tap Difference

169 170 171 172 169 170 171 172 169 170 171 172

9 1 1 4 2 2 3 -2 -1 -2 +2

10 124 125 -4 2 127 126 +1 -3 -1 -3

11 65 96 -3 1 66 97 -2 -1 -1 +2

 

The remaining events which don't appear in both lists are events which are, due to the variations in the bias, either below the threshold, or are no longer the local maximum.