For those interested in figuring out what is needed to address real crop production issue, as opposed to pretty pictures or hobby (movies of farming operations), plan on ending up with a hyperspectral VNIR drone. Here is one which was just announced. http://files.constantcontact.com/8abb5327be/b98849a7-3009-4d8b-9d59-67e3d1c475c1.pdf The drone and imager are not inexpensive, the software takes some expertise, etc. But when you see a weed patch, you'll know the species. In a field, you'll be able to calculate the percentage of reflective surface area by species, by crop or weeds - and follow changes over the growing season. You'll be able to derive planting/crop emergence statistics on each row of your planter, in different soil types, etc. Hard data changes one's discussion with seed companies and chemical companies. You can also do things such as finding cows hiding in the bush or under trees (or as the military does finding people hiding in ambush). So consider laying out your drone and software purchases to get there.