Quote - Ok, I am looking at the Lux Sample File.
LightGroup "sun"
LightSource "sunsky"
   "float gain" [0.050000]
   "vector sundir" [0.965955 -0.026948 0.257303]

   "float relsize" [1.000000]
   "float turbidity" [2.000000]

Could some in the know do a quick explaination?

I am guessing that "vector sundir" [0.965955 -0.026948 0.257303] transitions it using the X,Y and Z Axis and that those values can be Pos or Neg.
Anyone know what order they are in?

TKS

 

If I follow the question correctly, it is X,Y,Z order.  It's just that Z is Up, not Y IIRC.