Method for collecting images, comprising: detecting change from the average in a parameter of a crop or field； determining location of the field or a region of it (specifically of a vehicle that collects images)； capturing images for a time interval associated with the parameter change； associating the images with the location and storing image and position data together. A second variation in a second crop attribute may be detected. The two alterations may occur simultaneously. Pictures may be still photographs or video frames in a range of electromagnetic (EM) radiation wavelengths (eg. light, infra-red), and may be used for agronomic or agricultural analysis. Wireless communication with a network server may be employed. Observed properties may include crop yield, crop moisture, plant nitrogen content, plant height or width, plant health or vigour, crop mass, crop volume, crop or grain loss, seed spacing, seed depth, planting acceleration levels, proportion of weeds. Crop features may be monitored using sensors that measure impact or transmittance or reflectance of microwaves. Sensors and cameras may be mounted on a vehicle or tower (eg. combined harvester, aircraft, sprayer, monopole) during harvest. Location may be identified using satellite navigation, GNSS, GLONASS, Galileo or global positioning system (GPS).
