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I am having trouble with downloading the S2 L2A bands see below my request script. The request runs but it returns an empty image when I open it in ArcMap?


Your assistance is appreciated, I just removed the Bearer token.


curl -X POST https://services.sentinel-hub.com/api/v1/process \

 -H 'Content-Type: multipart/form-data' \

 -H 'Authorization: \

 --form-string 'request={

  "input": {

    "bounds": {

      "geometry": {

        "type": "Polygon",

        "coordinates": [

          [

            [

              387586.974469,

              8098945.900398

            ],

            [

              387884.086646,

              8097476.83939

            ],

            [

              389674.763248,

              8097959.748413

            ],

            [

              389409.287272,

              8099351.638973

            ],

            [

              387586.974469,

              8098945.900398

            ]

          ]

        ]

      },

      "properties": {

        "crs": "http://www.opengis.net/def/crs/EPSG/0/32737"

      }

    },

    "data": [

      {

        "dataFilter": {

          "timeRange": {

            "from": "2023-06-16T00:00:00Z",

            "to": "2023-06-16T23:59:59Z"

          },

          "mosaickingOrder": "mostRecent"

        },

        "type": "sentinel-2-l2a"

      }

    ]

  },

  "output": {

    "width": 104.12118271595553,

    "height": 93.89618236811039,

    "responses": [

      {

        "identifier": "default",

        "format": {

          "type": "image/tiff"

        }

      }

    ]

  }

}' \

 --form-string 'evalscript=//VERSION=3



function setup() {

  return {

    input: [

      {

        bands: ["B01","B04","B07","B09","B02","B05","B08","B11","B03","B06","B12","B8A"],      

        units: "REFLECTANCE",            

      }

    ],

    output: [

      {

        id: "default",

        bands: 12,

        sampleType: "UINT16",        

        noDataValue: 0,

      },    

    ],

    mosaicking: "SIMPLE",

  };

}





function evaluatePixel(sample) {

    let val = [sample.B01, sample.B02, sample.B03, sample.B04, sample.B05, sample.B06, sample.B07, sample.B08, sample.B8A, sample.B09, sample.B1972, sample.B12];

    return val;

}



'

Hi Rickus,


Thanks for the question, for Sentinel-2 optical data, the relation between DN and REFLECTANCE (default unit) is: DN = 10000 * REFLECTANCE so in your evalscript you need to multiply each sample.[band] by 1000 to return the surface reflectance data in UINT16 format. For more info, I recommend reading this part of the docs.


Below is also the correct evalscript which will return an image for you!


//VERSION=3

function setup() {

  return {

    input: [

      {

        bands: ["B01","B04","B07","B09","B02","B05","B08","B11","B03","B06","B12","B8A"],      

        units: "REFLECTANCE",            

      }

    ],

    output: [

      {

        id: "default",

        bands: 12,

        sampleType: "UINT16",        

      },    

    ],

  };

}





function evaluatePixel(sample) {

    let val = [10000 * sample.B01, 10000 * sample.B02, 10000 * sample.B03, 10000 * sample.B04, 10000 * sample.B05, 10000 * sample.B06, 10000 * sample.B07, 10000 * sample.B08, 10000 * sample.B8A, 10000 * sample.B09, 10000 * sample.B11, 10000 * sample.B12];

    return val;

}

Thanks William, that has solved the problem, appreciate the help.

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