Sent you Mike's number. He'll be able to answer your questions. He basically told me that it's the way the Autofarm base stations do their survey. They're geared toward portability so in order to be auto-steering in a short amount of time after initial power-up of the base station, the base does not survey it's 'real-world' position. It instead surveys down to a suitable resolution and then, in effect, lays down it's own grid over the earth. Obviously, this grid does not necessarily line up with the 'real' grid. This is why any logged data is shifted from the boundary. I'm sure Mike will explain it much better than I did, but that's basically the gist of it. |