The satellite reads one clear day, and the field card shows five indices
A farm whose boundary is mapped can now be measured from Sentinel-2 one clear day at a time. The first version averaged five days into a single picture, and on a four hectare farm that average carried no usable ground for four months while one clear day in August carried hundreds of usable pixels over the same fields. Averaging was hiding the days that could be read.
The field card reports five indices for the day it measured: NDVI for green cover, SAVI and EVI for ground that is not fully covered, NDMI for water in the canopy, and NDRE for early nutrient stress. Each one states the day, which ground the clouds masked out, and what the index cannot tell you.
When a day is too cloudy to measure, the card says so for that day instead of repeating an older reading as if it were new. Live for mapped farms on the web app.