The best way to get information about all the available scenes in a specific area is to use our Catalog service API, which will give you detailed geospatial information for each tile, that you can control by specifying fields, limits and other properties. For this specific use case, it is most useful to use the distinct parameter with date, which will return a list of the available dates for your requested BBOX and time range. To make this Catalog API request, import the following CURL request to Postman. You will need to authenticate the request with a token.
curl -X POST 'services.sentinel-hub.com/api/v1/catalog/search' \
-header 'Authorization: Bearer <your access token>' \
-header 'Content-Type: application/json' \
-data-raw '{
"bbox": [13,45,14,46],
"datetime": "2019-12-10T00:00:00Z/2020-12-15T00:00:00Z",
"collections": ["sentinel-1-grd"],
"limit": 50,
"distinct": "date"
}'
In the curl request above, the first line is the URL for the request, which you only need to change if you’re using data collections on different deployments. The first header is where you add your access token; if you authenticate the collection or the request in Postman, the token will be automatically added. The second header is where you specify the desired output, which in this case, is a JSON file. In data-raw, you will specify the bbox, time range (datetime), data collection (collections), limit (the upper limit of the number of results), and with the line "distinct":"date", you will limit your results to only include information on the acquisition date. Consult the Catalog API reference to learn more about the available parameters.
The result for the CURL request above will look like this:
{
"type": "FeatureCollection",
"features": [
"2019-12-10",
"2019-12-11",
"2019-12-12",
"2019-12-15"
],
"links": [
{
"href": "http://services.sentinel-hub.com/api/v1/catalog/search",
"rel": "self",
"type": "application/json"
}
],
"context": {
"limit": 50,
"returned": 4
}
}
At the beginning of the result, you can see all the available dates listed for your request.
It’s also possible to search the available scenes using OGC WFS request, which might be a bit easier to use, but gives you much less search control.
To make a WFS request, you will need to add your INSTANCE_ID, specify the bbox, timerange (TIME), data collection (TYPENAMES), coordinate system (srsName) and a request type. Read more on the parameters here. An example WFS request would look like this:
https://services.sentinel-hub.com/ogc/wfs/INSTANCE_ID?REQUEST=GetFeature&srsName=EPSG:3857&TYPENAMES=DSS2&BBOX=3238005,5039853,3244050,5045897&TIME=2019-02-11/2019-02-12
You can test the WFS examples with different parameters and inspect the results instantly here.
Note that you can also use the MAXCC parameter (maximum cloud coverage) in this call to filter for cloudless data. Use FEATURE_OFFSET parameter to control the starting point within the returned features and MAXFEATURES parameter - the maximum number of parameters of features to be returned by a single request.
As a result you will get a list of all the available scenes for the chosen location in JSON format (or XML if set so). Some of the dates may be duplicated if there are two scenes available in the area. You should simply ignore these duplications.
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