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Hi,


I can’t understand why S2-L2A raw data downloaded via EO Browser have different pixel size from raw data downloaded via API request. I’ll try to show you better what I mean.


I managed to download all S2-L2A’s raw bands value following the example shown in Sentinel Hub Process API — Sentinel Hub 3.3.2 documentation (sentinelhub-py.readthedocs.io). In addition to this, being that the maximum spatial resolution for S2-L2A is 10m (as documentation said, the bands with lower resolutions will be automatically upscaled), I set resolution = 10, when specifying bbox size.



resolution = 10

betsiboka_bbox = BBox(bbox=betsiboka_coords_wgs84, crs=CRS.WGS84)

betsiboka_size = bbox_to_dimensions(betsiboka_bbox, resolution=resolution)



Checking the .TIFF file (2021-09-07.tiff) via QGIS, the pixel size seems to correspond.


10m

When downloading the same raw data via EO Browser (I used a .geoJSON polygon to call for the same bbox), I get images with different pixel size.


eo

This is what I get when I open “B01” and all the other bands.


7m

Shouldn’t I have the same raw data? Can someone help me understanding why I get this?


Thanks a lot for the help!


2021-09-07.tiff (4.5 KB)
2021-09-07-00_00_2021-09-07-23_59_Sentinel-2_L2A_B01_(Raw).tiff (1.3 KB)

Dear,

if you inspect the settings carefully you will see that below the selected Coordinate system (WGS84) also the resolution is given (in your case 0.2 sec/0.3 sec per pixel). This 0.3 sec will translate to a different resolution in m depending on where on earth you download the data (for betsiboka_bbox roughly the 7.4 meter you get in QGis when inspecting a pixel).

In order to download the data in the same resolution in EO Browser as you have selected in the notebook (10m) you have to

  • switch the coordinate system to Popular Web Mercator (EPSG: 3857) (this works only without an uploaded geometry)
  • be on a high zoom level ( try 14 or more) and have Image resolution High selected.

Best

With the latest EO Browser deploy (v3.34.0) we now also offer custom resolution (you can set the exact resolution in m you want to download) and the UTM coordinate system in the Analytical image download.

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