Which drone do you need for weed detection?

The same question comes up almost every week: which drone do I need to have my fields scanned for weed detection? The answer is more nuanced than a brand name or a price tag. What matters is whether the imagery has the right level of detail so the AI can distinguish every individual weed from the crop.

GSD: the number that matters most

The DJI Mavic 3 Multispectral is today's workhorse for most of our contractors and certified pilots. The device combines a 4/3" sensor with a mechanical shutter, which delivers sharp imagery even at higher flight speeds — and all of that at a very accessible price. For larger areas we often see the Matrice RTK deployed, with a heavier camera payload.

GSD is a combination of the sensor (resolution and size), the lens, and the flight height. A 20 MP camera at 80 metres gives a very different result than the same camera at 30 metres. In practice we usually fly between 40 and 70 metres, depending on the crop and the position of the sun.

For everyday use in arable farming, the DJI Mavic 3 Multispectral is the most reliable choice: enough resolution, a decently sized sensor, and RTK-GPS for accurate positioning.

Which models work in practice

The DJI Mavic 3 Enterprise is today's workhorse for most of our contractors and certified pilots. The device combines a 4/3" sensor with a mechanical shutter, which delivers sharp imagery even at higher flight speeds. For larger areas we often see the Matrice 350 RTK deployed, with the same or a heavier camera payload.

Consumer drones such as a regular Mavic Air or Mini do reach the required GSD, but lack RTK positioning. As a result, the geolocation of the imagery isn't accurate enough to build reliable task maps for spot spraying. For anyone who wants to scan their own field occasionally that can work, but keep in mind it won't deliver a good spraying result.