We’ve been converting cameras for NDVI vegetation and crop analysis for a few years now, and we’re happy to finally offer official NDVI conversions for all of our regular supported cameras as well as for most action cameras and drone cameras.
A traditional NDVI captures the red and infrared channel from which an index is generated to measure vegetation health. This index takes advantage of the photosystems in plant leaves that absorb blue and red light for photosynthesis and reflect green and infrared strongly to avoid overheating. By calculating the ratio of red to infrared absorption, it is possible to assess the health of the photosystem in the plant. Technically, because red and infrared register on the red channel of a camera sensor, it is impossible to isolate these two signals from a single capture, so it’s necesarry to either take two successive images, or shoot with two cameras side by side. It would be impossible to switch filters on a drone as it is flying, and having a two cameras setup doubles the weight and cost of the system and can add parallax.
With recent developments in our field, we can now taking advantage of the blue absorption peak of the plant with a dual band pass filter that transmits blue and infrared. This allows for an NDVI to be calculated using the blue and red channels from a single image, which represent the blue and infrared absorption, respectively. Images can be analyzed with the free online tool Infragram or the free ImageJ.
We can install the NDVI filter in any standard camera as well as most GoPros and Drone action cameras, you can find those here.