Online Masterclass:
In this episode, the Roswell Flight Test Crew continues to explore the use of drones in agriculture with Dr. Gregory Crutsinger of Scholar Farms. The focus of this outing is how to capture and and interpret multispectral images, which sample narrow bands of visible light, as well as near-infrared light, to indicate the health of crops through a process called normalized difference vegetative index, or NDVI. They test the technique at the Stoller Family Estates vineyards in the Oregon wine country. The imagery is captured by a Parrot Disco Pro Ag drone, which incorporates a light sensor on the top of the aircraft, to measure the total amount of light falling on the fields, so that the light reflected by the plants can be calibrated to yield consistent results, even as lighting conditions change. The data is then analyzed using Pix4D to create an orthomosaic map and define ratios between the reflectance of different bands of visible and infrared light.