Hi Chris,

Those are properties of your INSCRayTrace:

double  DeadRayErrors [get]

double  DeadRayThreshold [get]

You find this in the Syntax Help file under: ZOSAPI > Tools > RayTrace > INSCRayTrace. But there isn't much documentation about it.

Here is a code snippet showing you how to call those properties:

# Setup and run the ray trace
NSCRayTrace = TheSystem.Tools.OpenNSCRayTrace()
NSCRayTrace.ClearDetectors(0)
NSCRayTrace.SplitNSCRays = True
NSCRayTrace.ScatterNSCRays = True
NSCRayTrace.UsePolarization = True
NSCRayTrace.IgnoreErrors = True
NSCRayTrace.SaveRays = False
NSCRayTrace.RunAndWaitForCompletion()
print('Lost energy (errors): ', NSCRayTrace.DeadRayErrors)
print('Lost energy (thresholds): ', NSCRayTrace.DeadRayThreshold)
NSCRayTrace.Close()
print('Finished ray trace')

Let me know if this helps.

Take care,

David