When output tiff on NX 8 and NX 11 using the same data there are many differences.
Solution This is a case were related to clipping. It happens when the data fell on a dot which was technically outside of the viewport so wasn't included in the rendered output. Slightly by increasing the viewport to overcome any potential clipping.
This logic is not implemented at higher resolutions as should be evident if you exported at 300dpi for example.
Hardware/Software Configuration Platform: INTL64
OS Version: XP64_SP2