you could check the following: .>X0 $#
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- if the surface/element tilt is too large 0cGO*G2Xr
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- enough analysis rays used? <[*%d~92z
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- have you used Coherent Data option under Detector setting. z2.9l?"rfQ
NY(z3G
Someone above was right about that the non-sequential mode only uses geometric rays but you could see inteference fringes using Coherent Data.