We normally use a Trimble FMX with RTK for drilling with vra seed maps. To allow for overlaps we use the prescription factor setting to reduce the rate slightly. Due to a problem with the drilling tractor (whilst being serviced at the dealers) we have been lent a Case Optum with an AFS Pro 700 screen with Centrepoint RTX to do the drilling. Firstly does the Case system have a prescription factor setting to adjust the variable rate prescriptions? Secondly what files does the Case system use for prescription maps - shapefiles or isoxml? The dealer is coming out tomorrow to set it all up but often the links between office computer and tractor are not understood by the mechanics or the salesmen!