A five-band camera pulls apart what the eye lumps together: hungry plants, thirsty plants, and plants already fighting something off.
The first flight of a contract builds the reference layer. Every pass after that is compared against it, so a change of two percent in canopy vigour is visible weeks before it is visible from the cab. Zones come back ranked worst first, with the acreage and the likely cause attached.
Most growers start here. Imaging on its own changes what you spray and when, even if we never put an application aircraft over the field.