The information which determines how a polygonmesh will be shaded is stored in the OBJ's normals. Some applications do not include this informations in the exported OBJs. Other applications include normals which are insufficient for good shading.

Reverse Normals

Reverses the normals of the OBJ. Use this if the FACT looks inverted (inside out) in the EIAS.

Calculate Normals

This option calculates new normals for the FACT based on the value in the Angle box. All polygons that share an edge with an angle larger than the value will be flat shaded; all polygons that share an edge with an angle smaller than the value will be smooth shaded.

Note: If you are not sure always do your first conversion without this option. Only use it when you discover any shading anomalies.