I would like to ask you what to do before using the Sentinel 2 data to extract NDVI

Optical Toolbox sen2cor
#1

dear,I would like to ask you what to do before using the Sentinel 2 data to extract NDVI, and which data is better L1C level, or L2A level?thank you!

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#2

The better data is L2A. Then after importing the image product to SNAP you need to resample the image and if you only need NDVI bands 4 and 8 would be enough. Choose band 4 to resample others from. After do reduce size of your data, define a Subset for the region of interest, with geographic coordinates.
Edit: leave also bands 2 and 3 to make a RGB composition. Always handy :slight_smile:

#3

thanks a lot:微笑:

#4

dear,Is radiation calibration and atmospheric correction required before extracting ndvi with Sentinel 2 L2A or is it necessary to perform radiation calibration and atmospheric correction when using landsat8image data to extract NDVI?

#5

I believe you should read the following manual http://step.esa.int/main/third-party-plugins-2/sen2cor/sen2cor_v2-8/
About Sentinel 2 L2A you don’t need to operate calibration or atmospheric correction (you will find that on the previous read). About landsat 8, I don’t have any experience, so I can’t advise you on that issue.

#6

thank you very much and best wishes.:smiley: