shell definition - orientation of thickness offset

G'day!

Does anybody know which way is top / bottom for shell thickness definition? see attached snapshot.

There is no preview and the help is hopeless. For me it's always a hit&miss exercise. I have to pick an option, render the mesh in 3d to check and in 99% of the cases change to opposite option. This is time consuming just adding to the list of unexpected crashes, ever-increasing filesize, other bugs and general slow speed when rendering the mesh in 3d.

Cheers!

Bud

SolidworksSimulation