I have heard of guys getting their scale factor by measuring a distance with a TS and then measuring it with a Gps and scaling accordingly. Trimble access has it where if you compute an inverse between two points, you can change the distance it shows you from grid or ground. The ground distance you get from there, points measured with gps, is that ground distance an accurate distance or has it just calculated a scale factor and given a predicted ground distance?

Hi,

Here you can see difference between ground and grid.

Cogo settings

Just click at Distance display and calculation