Sentinel1 image result is different when using wmsrequest or evalscript for the same bbox

I have the following bbox:

bbox_coords_wgs=[-47.949734553694725, -8.746513680257486,-47.9345985129475, 
 -8.717573061584929]

I’m using evaluate script in order to retrieve image for this bounding box:

#Time Interval for images
time_interval = ('2020-12-31', '2021-01-10')


evalscript = """
    //VERSION=3
    

    return [VV,VH, dataMask]
"""

time_interval = time_interval

request = SentinelHubRequest(
    data_folder='sen1_test3',
    evalscript=evalscript,
    input_data=[
        SentinelHubRequest.input_data(
            data_collection=DataCollection.SENTINEL1_IW,
            time_interval=time_interval,
            other_args = {"dataFilter":{"demInstance":"COPERNICUS_30"},"processing":{"orthorectify":True,"backCoeff":"SIGMA0_ELLIPSOID"}}
        )
    
    ],
    responses=[
        SentinelHubRequest.output_response('default', MimeType.TIFF)
    ],
    bbox=bbox,
    config=config
)

image = request.get_data(save_data=True)

plot_image(image[0], factor=1)

the result image looks like this:
image

Then when I do the same with WMSrequest I get different shape (the correct shape):



s1_request = WmsRequest(
    data_collection=DataCollection.SENTINEL1_IW,
    layer='TRUE-COLOR-S1-IW',
    bbox=bbox,
    time=('2020-11-01', '2021-01-10'),
    width=bbox_size[0],
    config=config
)

s1_data = s1_request.get_data()

image

is important to mention that in the wms request the bands that suppose to be return are:

return [VV,VH, 2 * VH, VV / VH / 100.0]

why is it different?

Best regards

Reut

Dear @reutkeller,

evalscript and wmsrequest describe completely different concepts so you should phrase your question more precisely.

Evalscript describes the processing flow to be done on the pixel level within the Sentinel Hub as described here:

wmsrequest is a Python wrapper around Sentinel Hub’s WMS OGC API and can refer to just about anything.

I would kindly suggest you spend some time checking the documentation and perhaps our Webinars, perhaps the one related to the “processng API” and the one related to the “Evalscript” (Custom script).

I feel that once you get familiar with the concepts, your understanding of the underlying data will get better and you will be able to answer a lot of these questions by yourself. And when providing questions to the Forum, you will be able to write them in such a manner that we will actually be able to asnwer them properly.

Best,
Grega

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