you could check the following: 0'c<EJ
_av%`bb&z9
- if the surface/element tilt is too large 0JKbp*H
f+-w~cN
- enough analysis rays used? 64hr|v
:q0C$xF
- have you used Coherent Data option under Detector setting. /,c9&it(M
T->O5t c
Someone above was right about that the non-sequential mode only uses geometric rays but you could see inteference fringes using Coherent Data.