What is the difference between calibrated and relative NDVI?
• Relative NDVI shows vigor variations relative to the vineyard of interest (lowest to highest vigor within that vineyard). This is useful for identifying patterns and segregating areas for different treatments or harvest. • Calibrated NDVI is produced on a fixed scale and therefore, in addition to the above uses, can be directly compared over time and across different locations. Calibrated NDVI also provides a measure of the scale of variability. Is the vineyard fairly uniform, or are there significant vigor variations? VineView applies calibration methods used by USDA scientists to provide consistent imaging products. Calibration also allows for other types of analyses such as change analysis (comparisons over time) and threshold analysis (comparisons of all vines to the “ideal” vines).
