0

I exported 2 raster bands of Sentinel II (band 4 and band 8) to calculate NDVI (B8-B4)/(B8+B4), these 2 rasters are in EPSG:32630 - WGS 84 / UTM zone 30N. I'm currently using QGIS 3.26.1.

When I try to use raster calculator to do this NDVI my resluts are really bad, here are parameters I putted in :

I'm supposed to have something that looks like what you can see on the left picture but I have what is on the right.

__________________desired result _____________________________________ result obtained enter image description here

5
  • 1
    Which version of QGIS do you use?
    – GisUser
    Commented May 9, 2023 at 14:02
  • 1
    please edit your question to explain exactly what you think is wrong with your output
    – Ian Turton
    Commented May 9, 2023 at 14:30
  • Used Bands seems good, Raster calculator runs so there is no error?
    – MarcM
    Commented May 9, 2023 at 14:37
  • I'm sorry I reversed the results in the text, I just edited it. @Matt Commented May 11, 2023 at 6:28
  • The results seem to be wrong because I have in result this kind of mixture between the 2 bands that you can see on the right image. I am trying to get something that looks like the one on the left. @MarcM Commented May 11, 2023 at 6:33

2 Answers 2

0

I found something that works, I don't know if that's the main reason why my operation didn't work.

When I wrote the question the layers obtained by exporting the Sentinel II data were in "jp2" format, I noticed that when I re-saved them in GeoTIFF and used the raster calculator, I didn't have this problem anymore.

0

I frequently have the same problem ... Formula for NDVI in raster calculator generates two 'twin images' as shown (QGis version 3.32.1-Lima, on Windows). Doing the exact same process in Saga-Gis as well as in 'SAGA Next Gen' (within Qgis toolbox) results in a correct one.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.