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by mikewhy 3133 days ago
Granted I'm just a software developer, we have a whole processing team of GIS people that can go into more detail. And we are focused on vineyards.

Here's a blog post we made to explain the difference, the jist is NDVI can change throughout the day while EVI is more stable: https://skysquirrel.ca/2017/07/evi-vs-ndvi-whats-difference/
1 comments
ruc0la 3133 days ago
Thank you guys I will check out the linked sites; I haven't purchased the drone yet. I do not want to spend, too much (1-2k in €) so maybe I will use a service instead. I am pretty familiar with GIS, and I use it on a regular basis for the orchard (I am experimenting with almond as we have a warmer microclimate here in the valley).
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tudorw 3132 days ago
here's a paper looking at which indexes work with corn, wheat and irrigation water, it's very likely each crop will have an index that is more accurate;

"The following spectral indices were examined: Difference Vegetation Index (DVI), Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI), Difference Water Index (DWI), Normalized Difference Water Index (NDWI), Difference Drought Index (DDI) and Normalized Difference Drought Index (NDDI). "

https://www.degruyter.com/downloadpdf/j/jengeo.2015.8.issue-...

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