This application hosts sensor based nitrogen recommendation algorithms which have been developed by researchers in each respective region. The calculations are based upon NDVI values retrieved from the GreenSeeker Sensor. The GreenSeeker is an active light sensor. It would be expected the NDVI from other actives sensors would be similar, but potentially not exactly the same. NDVI from passive sensors or cameras should be used with caution as the same level of calibration that can come from an active sensor is more challenging.