The NDVI toolbox allows you to customize the way you visualize your NDVI data. You can use it to eliminate portions of the NDVI index range that aren't used within the data or to increase the dynamic range of the data you care about. You can also view a histogram of your field's data, which gives you a quick snapshot of field health as a function of acreage.
By default, the NDVI toolbox displays your NDVI data with a 5 bin "equal area" color map. With these settings, your field data is broken into 5 nominally equal-acreage buckets and the index is color-mapped from red to green. This mode enhances NDVI contrast across your field and makes it easy to spot differences.
Inevitably, your drone will capture images of roads, buildings, and equipment that does not need to be considered in your field's NDVI analysis. Conversely, you may also capture imagery of extremely vigorous vegetation adjacent to your fields, such as sloughs, ditches and buffer areas. You may use the NDVI toolbox to omit this data from the analysis by adjusting the positions of the left and right sliders.
For example, move the slider on the left until roads disappear (turn black) from your data-set. They will no longer be counted as acreage, or in your overall crop health calculations and statistics. Move the slider on the right until no crops other than your own are green. You've now omitted neighboring vegetation that may be more advanced than your own. What remains is a narrow, "zoomed in", view of your field's data colored from red to green.
Getting more specific, here's another example of things you can do with the NDVI toolbox. Generally, water measures an NDVI value around -1. For this reason, it can be easily detected and measured. Simply slide the right-hand to -.75 and leave the left-hand slider at -1. Then, set the bin count to 1. This, generally, represents the water in your field. Of course, this is simply an estimate and can be affected by other objects in the field. You can tune the position of the right-hand slider based on your knowledge of the field, its low spots, and its current condition to refine the estimate.
In the NDVI Tool box gives the ability to set up Management Zones for building out precision prescriptions. Checking the box for for Zone management, turns on the functionality. The slide bar will allow the user to determine the level of detail to use in for the zones. If this is your first time try running the zones at a couple of different levels of detail to understand how this works. Click on the Gear icon next to the slide bar to start building Management Zone Polygons. These polygons can then be exported to a folder on the PC where the can then be imported in to a number of Farm Management Tools. The user can also click on the "RX" button to build out a simple prescriptions that when exported and then imported will export the prescription details and when imported in to the farm management tools.