What is Multispectral Scanning?
Multispectral imaging captures and records light across a range of wavelengths within the electromagnetic spectrum - including those outside of the visible spectrum, such as near infrared and red edge.
As a result, multispectral imaging provides the ability to extract additional information which the human eye or standard industrial vision cameras fail to capture.
This extra information has tremendous value to those in agriculture and land management.
By having access to multispectral data - and the subsequently obtained Vegetation Index data such as NDRE and NDVI (more on this later) - farmers can obtain deeper, more accurate and timely insights to help identify problem areas in a field, such as sections that are experiencing stress due to disease, pests, water stress, or nutrient deficiencies.
In turn, this data enables farmers to detect issues early and make informed and more targeted management decisions that can improve crop yields, save resources, and reduce waste and costs.
Multispectral Bands and their Insights
As we've mentioned, multispectral imaging captures images in various spectral bands - or ranges of wavelengths - of the electromagnetic spectrum.
Some of the most commonly used bands for multispectral imaging in agriculture, forestry, and land management include:
Isolating these bands is useful for analysing an object's spectral signature. In agriculture, this process helps to monitor plant health.
For example, healthy plants reflect a smaller quantity of red light but a larger amount of near-infrared light (which humans can't detect, but multispectral imaging can), whereas the opposite is true for stressed or dead plants.
Multispectral cameras are able to present us with a separate photograph of each band.
Therefore, by using multispectral imaging, the levels of near-infrared can be observed, enabling agriculture professionals to monitor plant health and track changes earlier to identify areas of a field that may require attention or specific areas that need fertilisation and water.
Images and data credit