Practical knowledge

Which cameras can be used for precision agriculture

Two major types of cameras can be used for estimating the health of plants: multispectral and modified cameras. PIX4Dmapper can process both types of imagery. The choice of filter/band depends entirely on the intent.

Example: For example, the red and NIR bands are most suited to compute NDVI (related to the health of the plant), and red edge bands are appropriate for the Chlorophyll Index (related to the amount of chlorophyll in the plant).

Multispectral, narrow band cameras

These cameras are designed for fidelity in order to be as accurate as possible when measuring the reflectance of objects. Multispectral cameras can come with sun irradiance sensors and/or a calibration target to properly estimate the incoming sunlight irradiance effect and compute absolute reflectance. For more information: Radiometric calibration target, Radiometric corrections.

Such cameras include Sequoia, Multispec 4C and Micasense RedEdge. For more information: How to process Sequoia imagery.

Modified standard cameras

By carefully changing the filters of a normal camera, it is possible to get wide band infrared measurements. However, it is critical to follow a certain workflow to obtain somewhat accurate relative measurements. Many companies offer to either modify cameras or sell already modified cameras. For more information: Camera Requirements for Precision Agriculture, How to set the band weights for modified cameras (NIR,R,G and NIR,G,B).

Important: It important to note that despite their low cost and easy availability, modified cameras' results are much more complicated to interpret, the accuracy is hard to assess and the results may vary significantly with time.