you could check the following: [?;L
mFxt +\
- if the surface/element tilt is too large 7,V_5M;t
[p}~M-$V8Y
- enough analysis rays used? Aayd3Ph0%
H\N}0^ea
- have you used Coherent Data option under Detector setting. 8G|?R#&
}9#GJ:x`
Someone above was right about that the non-sequential mode only uses geometric rays but you could see inteference fringes using Coherent Data.