you could check the following: i1sc oxX3\
zS?L3*u
- if the surface/element tilt is too large zg^5cHP\
^91k@MC
- enough analysis rays used? @@! R
Iq!
cOS|B1xG
- have you used Coherent Data option under Detector setting. @ VJr0
ukZL
Someone above was right about that the non-sequential mode only uses geometric rays but you could see inteference fringes using Coherent Data.