We have a Trimble unit we use to collect equipment.

We collect the data in WGS84 and differentially correct it and then reproject it to a state plan coordinate system.

The points always shift the same distance in the same direction after the reprojection.

What is the reason for this?

Thanks.

We have a Trimble GPS unit we use to collect system assets.

We collect the data in WGS84 and differentially correct it, and then reproject it into our State Plane Coordinate System.

The resulting points always shift the same distance in the same direction after the reprojection.

Any idea what could cause this?