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Hi there,

I’m using the sentinelhub process api to download raw sentinel-2 L2A imagery.

I noticed that pixel values are a bit different from other sources.


image

For example each pixel is 1000 units less than the same values from google earth engine.


Is there something wrong with my process?


P.S. here’s my evalscript


“”"

//VERSION=3


    function setup() {

        return {

            input:  {

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

                units: "DN"

            }],

            output: {

                bands: 12,

                sampleType: SampleType.UINT16,

            }

        };

    }



    function evaluatePixel(sample) {

        return  sample.B01, sample.B02, sample.B03, sample.B04, sample.B05, sample.B06, sample.B07, sample.B08, sample.B8A, sample.B09, sample.B1972, sample.B12];

    }

"""

I am guessing this is due GEE not yet implementing the Sentinel-2 baseline changes as described in this post:




Sentinel-2 processing baseline changes and harmonizeValues News


As you wrote, there should be no changes in reflectance values if the parameter will stay as defalut, but I noticed that NDVI calculated on data acquired starting from 25 January has much lower values compared to earlier images. Do you know what this could be due to?

By default, Sentinel Hub is harmonizing the values so that they are consistent before and after the change. If you want to get “original” data, you should use “harmonizeValues” parameter. But do note that it will be difficult to compare the data from i.e. February 2021 and February 2022.

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