I’m confused with the products derived with Sen2Cor.
I processed an S2 image in sen2cor at 10m resolution to get L2A. The user guide says that “Inputs for the 10m product processing are the four 10m bands B02-B04 and
B08” and "… The 10m product processing covers thus only four optical channels. The other
channels, not used for the calculation will be omitted " so I’m expecting to get a 10m resolution product with only the bands B02-B04 and B08, which is exactly what I need. However, the product I got after running sen2cor consists of Bands 2, 3, 4, 5, 6, 7, 8, 8A, 11 and 12. So, when subsetting the data over a study area, SNAP indicates that the product has different resolution that I should do a resampling before subsetting. What’s happening here, am I missing a step? Is it possible to do resampling then subsetting then sen2cor? It would be helpful to have a clear/graphical workflow.
from the Sen2cor user guide:
"Inputs for the 10m product processing are the four 10m bands B02-B04and B08, an optional 10m DEM an up-sampled Scene Classification and a Visibility Index map, both up-sampled from 20m. As the WV influence is very small, only the scene-average WV needs to be used for the surface reflectance retrieval. The 10m product processing covers thus only four optical channels. The other channels, not used for the calculation will be omitted. If a 20 m processing has already been performed in ahead, these data will be used as input. Else, a 20 m resolution will be performed first, in order to have access to the input data "
It is also clarified in the ATBD:
If you open the folder with your L2 data, in the folder GRANULE/{specificGranule}/IMG_DATA you will find two folders with the results at 20 and 10m: R10m and R20m.
When opening this product, the reader in SNAP loads the reflectance of some bands at 20 m. By this reason, you have some bands at 10 and other at 20 meters resolution. You will see also that your product has some angle bands at 5000m resolution. To be able to subset the product, as SNAP says, it is needed to resample it first: Menu->Raster->GeometricOperations->Resampling (you can select the size “by reference band from the source product” and choose one of the bands at 10m).
You could also remove the R20m folder (or rename it) and only the bands at 10m will be opened in SNAP.
Hi obarrilero, I need to understand the difference beteween corrections resolutions, Can you help me?
if i apply a 10m corrections, the rest of bands are not corrections? how i can to correct all bands of a complete sentinel2 imagen? Please!
