NDVI is an acronym for Normalised Difference Vegetation Index. It’s a very interesting measure of plant photosynthesis and health derived from measuring the difference in near-infrared and visual reflectance. I’ve recently been exploring its use for plant monitoring; here are a few calibration images.
[NDVI=\frac{NIR-VIS}{NIR+VIS}]
The original image is on the left, with NDVI on the right
These images were shot using a full-spectrum modified Sony A7 camera with OM Zuiko 21mm/3.