diff --git a/src/pg_to_evalscript/conversion.py b/src/pg_to_evalscript/conversion.py
index 6179efb..a0a8315 100644
--- a/src/pg_to_evalscript/conversion.py
+++ b/src/pg_to_evalscript/conversion.py
@@ -86,13 +86,13 @@ def convert_from_process_graph(
     bands_dimension_name="bands",
     temporal_dimension_name="t",
     encode_result=True,
-    bands_metadata=[],
+    bands_metadata={},
 ):
     all_nodes_valid, subgraphs = check_validity_and_subgraphs(
         process_graph, temporal_dimension_name, bands_dimension_name, user_defined_processes=user_defined_processes
     )
     if all_nodes_valid:
-        nodes, input_bands, initial_data_name = generate_nodes_from_process_graph(
+        nodes, input_bands, initial_data_names = generate_nodes_from_process_graph(
             process_graph,
             bands_dimension_name,
             temporal_dimension_name,
@@ -102,7 +102,7 @@ def convert_from_process_graph(
         evalscript = Evalscript(
             input_bands,
             nodes,
-            initial_data_name,
+            initial_data_names,
             n_output_bands=n_output_bands,
             sample_type=sample_type,
             units=units,
@@ -165,8 +165,8 @@ def generate_nodes_from_process_graph(
     )
 
     nodes = []
-    input_bands = None
-    initial_data_name = None
+    input_bands = []
+    initial_data_names = {}
 
     for node_id in execution_order:
         process_id = process_graph[node_id]["process_id"]
@@ -174,8 +174,10 @@ def generate_nodes_from_process_graph(
         child_nodes = None
 
         if process_id == "load_collection":
-            input_bands = arguments.get("bands")
+            bands_for_datasource = arguments.get("bands")
             initial_data_name = "node_" + node_id
+            input_bands.append({"datasource": initial_data_name, "bands": bands_for_datasource})
+            initial_data_names[node_id] = initial_data_name
             continue
         elif process_id == "save_result":
             continue
@@ -257,4 +259,4 @@ def generate_nodes_from_process_graph(
             bands_dimension_name=bands_dimension_name,
         )
         nodes.append(node)
-    return nodes, input_bands, initial_data_name
+    return nodes, input_bands, initial_data_names
diff --git a/src/pg_to_evalscript/evalscript.py b/src/pg_to_evalscript/evalscript.py
index be701d9..acf4ed3 100644
--- a/src/pg_to_evalscript/evalscript.py
+++ b/src/pg_to_evalscript/evalscript.py
@@ -20,7 +20,7 @@ def __init__(
         self,
         input_bands,
         nodes,
-        initial_data_name,
+        initial_data_names,
         n_output_bands=1,
         sample_type="AUTO",
         units=None,
@@ -30,11 +30,11 @@ def __init__(
         datacube_definition_directory="javascript_datacube",
         output_dimensions=None,
         encode_result=True,
-        bands_metadata=[],
+        bands_metadata={},
     ):
         self.input_bands = input_bands
         self.nodes = nodes
-        self.initial_data_name = initial_data_name
+        self.initial_data_names = initial_data_names
         self.n_output_bands = n_output_bands
         self.sample_type = sample_type
         self.units = units
@@ -47,7 +47,7 @@ def __init__(
         self.bands_metadata = bands_metadata
 
     def write(self):
-        if self.input_bands is None:
+        if any(datasource_with_bands["bands"] is None for datasource_with_bands in self.input_bands):
             raise Exception("input_bands must be set!")
         newline = "\n"
         tab = "\t"
@@ -55,7 +55,7 @@ def write(self):
 //VERSION=3
 function setup() {{
   return {{
-    input: [{",".join([f"'{band}'" for band in self.input_bands])}],
+    input: [{",".join([f"{datasource_with_bands}" for datasource_with_bands in self.input_bands])}],
     output: {{ bands: {self.n_output_bands}, sampleType: "{self.sample_type}"{f", units: '{self.units}'" if self.units is not None else ''} }},
     mosaicking: "{self.mosaicking}"
   }};
@@ -103,10 +103,24 @@ def write_ndarray_definition(self):
         return pkgutil.get_data("pg_to_evalscript", f"javascript_datacube/ndarray.js").decode("utf-8")
 
     def write_datacube_creation(self):
-        return f"let {self.initial_data_name} = new DataCube(samples, '{self.bands_dimension_name}', '{self.temporal_dimension_name}', true, {json.dumps(self.bands_metadata)}, scenes)"
+        datacube_creation = ""
+        if len(self.input_bands) > 1:
+            for datasource_with_bands in self.input_bands:
+                datasource_name = datasource_with_bands["datasource"]
+                datacube_creation += f"let {datasource_name} = new DataCube(samples.{datasource_name}, '{self.bands_dimension_name}', '{self.temporal_dimension_name}', true, {json.dumps(self.bands_metadata[datasource_name] if self.bands_metadata is not None and len(self.bands_metadata) > 0 else None)}, scenes)\n\t"
+        else:
+            datasource_with_bands = self.input_bands[0]
+            datasource_name = datasource_with_bands["datasource"]
+            datacube_creation += f"let {datasource_name} = new DataCube(samples, '{self.bands_dimension_name}', '{self.temporal_dimension_name}', true, {json.dumps(self.bands_metadata[datasource_name] if self.bands_metadata is not None and len(self.bands_metadata) > 0 else None)}, scenes)\n\t"
+
+        return datacube_creation
 
     def write_runtime_global_constants(self):
-        return f"const INPUT_BANDS = {self.input_bands};"
+        all_bands = []
+        for datasource_with_bands in self.input_bands:
+            all_bands.extend(datasource_with_bands["bands"])
+
+        return f"const INPUT_BANDS = {list(set(all_bands))};"
 
     def write_update_output(self):
         if self._output_dimensions is None:
@@ -120,7 +134,13 @@ def write_update_output(self):
         size_without_original_temporal_dimensions = reduce(
             lambda x, y: x * y, sizes_without_original_temporal_dimensions, 1
         )
-        collection_scenes_length = "* collection.scenes.length" * number_of_original_temporal_dimensions
+        if len(self.input_bands) > 1:
+            collection_scenes_length = (
+                "* Object.values(collection).reduce((acc, val) => acc + val.scenes.length, 0)"
+                * number_of_original_temporal_dimensions
+            )
+        else:
+            collection_scenes_length = "* collection.scenes.length" * number_of_original_temporal_dimensions
         number_of_final_dimensions = len(self._output_dimensions) + 1 if self.encode_result else 0
         return f"""
 function updateOutput(outputs, collection) {{
@@ -131,13 +151,18 @@ def write_update_output(self):
 
     def write_output_variable(self):
         if len(self.nodes) == 0:
-            return self.initial_data_name
+            return "_".join(self.initial_data_names.values())
         return self.nodes[-1].node_varname_prefix + self.nodes[-1].node_id
 
     def determine_output_dimensions(self):
         dimensions_of_inputs_per_node = defaultdict(list)
+        all_bands = []
+        for datasource_with_bands in self.input_bands:
+            if datasource_with_bands is not None and datasource_with_bands["bands"] is not None:
+                all_bands.extend(datasource_with_bands["bands"])
+
         initial_output_dimensions = [
-            {"name": self.bands_dimension_name, "size": len(self.input_bands) if self.input_bands is not None else 0},
+            {"name": self.bands_dimension_name, "size": len(set(all_bands)) if self.input_bands is not None else 0},
             {"name": self.temporal_dimension_name, "size": None, "original_temporal": True},
         ]
 
@@ -147,7 +172,7 @@ def determine_output_dimensions(self):
         dimensions_of_inputs_per_node[self.nodes[0].node_id].append(initial_output_dimensions)
 
         for node in self.nodes:
-            output_dimensions = node.get_dimensions_change(dimensions_of_inputs_per_node[node.node_id])
+            output_dimensions = node.get_dimensions_change(dimensions_of_inputs_per_node[node.node_id] if len(dimensions_of_inputs_per_node[node.node_id]) > 0 else [initial_output_dimensions])
             for dependent in node.dependents:
                 dimensions_of_inputs_per_node[dependent].append(output_dimensions)
 
diff --git a/tests/integration_tests/fixtures.py b/tests/integration_tests/fixtures.py
index afb090c..b275098 100644
--- a/tests/integration_tests/fixtures.py
+++ b/tests/integration_tests/fixtures.py
@@ -47,133 +47,135 @@
 }
 
 
-bands_metadata = [
-    {
-        "name": "B01",
-        "common_name": "coastal",
-        "center_wavelength": 0.4427,
-        "full_width_half_max": 0.021,
-        "openeo:gsd": {"value": [60, 60], "unit": "m"},
-    },
-    {
-        "name": "B02",
-        "common_name": "blue",
-        "center_wavelength": 0.4924,
-        "full_width_half_max": 0.066,
-        "openeo:gsd": {"value": [10, 10], "unit": "m"},
-    },
-    {
-        "name": "B03",
-        "common_name": "green",
-        "center_wavelength": 0.5598,
-        "full_width_half_max": 0.036,
-        "openeo:gsd": {"value": [10, 10], "unit": "m"},
-    },
-    {
-        "name": "B04",
-        "common_name": "red",
-        "center_wavelength": 0.6646,
-        "full_width_half_max": 0.031,
-        "openeo:gsd": {"value": [10, 10], "unit": "m"},
-    },
-    {
-        "name": "B05",
-        "center_wavelength": 0.7041,
-        "full_width_half_max": 0.015,
-        "openeo:gsd": {"value": [20, 20], "unit": "m"},
-    },
-    {
-        "name": "B06",
-        "center_wavelength": 0.7405,
-        "full_width_half_max": 0.015,
-        "openeo:gsd": {"value": [20, 20], "unit": "m"},
-    },
-    {
-        "name": "B07",
-        "center_wavelength": 0.7828,
-        "full_width_half_max": 0.02,
-        "openeo:gsd": {"value": [20, 20], "unit": "m"},
-    },
-    {
-        "name": "B08",
-        "common_name": "nir",
-        "center_wavelength": 0.8328,
-        "full_width_half_max": 0.106,
-        "openeo:gsd": {"value": [10, 10], "unit": "m"},
-    },
-    {
-        "name": "B8A",
-        "common_name": "nir08",
-        "center_wavelength": 0.8647,
-        "full_width_half_max": 0.021,
-        "openeo:gsd": {"value": [20, 20], "unit": "m"},
-    },
-    {
-        "name": "B09",
-        "common_name": "nir09",
-        "center_wavelength": 0.9451,
-        "full_width_half_max": 0.02,
-        "openeo:gsd": {"value": [60, 60], "unit": "m"},
-    },
-    {
-        "name": "B11",
-        "common_name": "swir16",
-        "center_wavelength": 1.6137,
-        "full_width_half_max": 0.091,
-        "openeo:gsd": {"value": [20, 20], "unit": "m"},
-    },
-    {
-        "name": "B12",
-        "common_name": "swir22",
-        "center_wavelength": 2.2024,
-        "full_width_half_max": 0.175,
-        "openeo:gsd": {"value": [20, 20], "unit": "m"},
-    },
-    {
-        "description": "Aerosol Optical Thickness map, based on Sen2Cor processor",
-        "name": "AOT",
-        "openeo:gsd": {"value": [10, 10], "unit": "m"},
-    },
-    {
-        "description": "Scene classification data, based on Sen2Cor processor, codelist",
-        "name": "SCL",
-        "openeo:gsd": {"value": [20, 20], "unit": "m"},
-    },
-    {
-        "description": "Snow probability, based on Sen2Cor processor",
-        "name": "SNW",
-        "openeo:gsd": {"value": [20, 20], "unit": "m"},
-    },
-    {
-        "description": "Cloud probability, based on Sen2Cor processor",
-        "name": "CLD",
-        "openeo:gsd": {"value": [20, 20], "unit": "m"},
-    },
-    {
-        "description": "Cloud probability, based on s2cloudless",
-        "name": "CLP",
-        "openeo:gsd": {"value": [160, 160], "unit": "m"},
-    },
-    {"description": "Cloud masks", "name": "CLM", "openeo:gsd": {"value": [160, 160], "unit": "m"}},
-    {
-        "description": "Sun azimuth angle",
-        "name": "sunAzimuthAngles",
-        "openeo:gsd": {"value": [5000, 5000], "unit": "m"},
-    },
-    {
-        "description": "Sun zenith angle",
-        "name": "sunZenithAngles",
-        "openeo:gsd": {"value": [5000, 5000], "unit": "m"},
-    },
-    {
-        "description": "Viewing azimuth angle",
-        "name": "viewAzimuthMean",
-        "openeo:gsd": {"value": [5000, 5000], "unit": "m"},
-    },
-    {
-        "description": "Viewing zenith angle",
-        "name": "viewZenithMean",
-        "openeo:gsd": {"value": [5000, 5000], "unit": "m"},
-    },
-    {"description": "The mask of data/no data pixels.", "name": "dataMask"},
-]
\ No newline at end of file
+bands_metadata = {
+    "node_loadcollection": [
+        {
+            "name": "B01",
+            "common_name": "coastal",
+            "center_wavelength": 0.4427,
+            "full_width_half_max": 0.021,
+            "openeo:gsd": {"value": [60, 60], "unit": "m"},
+        },
+        {
+            "name": "B02",
+            "common_name": "blue",
+            "center_wavelength": 0.4924,
+            "full_width_half_max": 0.066,
+            "openeo:gsd": {"value": [10, 10], "unit": "m"},
+        },
+        {
+            "name": "B03",
+            "common_name": "green",
+            "center_wavelength": 0.5598,
+            "full_width_half_max": 0.036,
+            "openeo:gsd": {"value": [10, 10], "unit": "m"},
+        },
+        {
+            "name": "B04",
+            "common_name": "red",
+            "center_wavelength": 0.6646,
+            "full_width_half_max": 0.031,
+            "openeo:gsd": {"value": [10, 10], "unit": "m"},
+        },
+        {
+            "name": "B05",
+            "center_wavelength": 0.7041,
+            "full_width_half_max": 0.015,
+            "openeo:gsd": {"value": [20, 20], "unit": "m"},
+        },
+        {
+            "name": "B06",
+            "center_wavelength": 0.7405,
+            "full_width_half_max": 0.015,
+            "openeo:gsd": {"value": [20, 20], "unit": "m"},
+        },
+        {
+            "name": "B07",
+            "center_wavelength": 0.7828,
+            "full_width_half_max": 0.02,
+            "openeo:gsd": {"value": [20, 20], "unit": "m"},
+        },
+        {
+            "name": "B08",
+            "common_name": "nir",
+            "center_wavelength": 0.8328,
+            "full_width_half_max": 0.106,
+            "openeo:gsd": {"value": [10, 10], "unit": "m"},
+        },
+        {
+            "name": "B8A",
+            "common_name": "nir08",
+            "center_wavelength": 0.8647,
+            "full_width_half_max": 0.021,
+            "openeo:gsd": {"value": [20, 20], "unit": "m"},
+        },
+        {
+            "name": "B09",
+            "common_name": "nir09",
+            "center_wavelength": 0.9451,
+            "full_width_half_max": 0.02,
+            "openeo:gsd": {"value": [60, 60], "unit": "m"},
+        },
+        {
+            "name": "B11",
+            "common_name": "swir16",
+            "center_wavelength": 1.6137,
+            "full_width_half_max": 0.091,
+            "openeo:gsd": {"value": [20, 20], "unit": "m"},
+        },
+        {
+            "name": "B12",
+            "common_name": "swir22",
+            "center_wavelength": 2.2024,
+            "full_width_half_max": 0.175,
+            "openeo:gsd": {"value": [20, 20], "unit": "m"},
+        },
+        {
+            "description": "Aerosol Optical Thickness map, based on Sen2Cor processor",
+            "name": "AOT",
+            "openeo:gsd": {"value": [10, 10], "unit": "m"},
+        },
+        {
+            "description": "Scene classification data, based on Sen2Cor processor, codelist",
+            "name": "SCL",
+            "openeo:gsd": {"value": [20, 20], "unit": "m"},
+        },
+        {
+            "description": "Snow probability, based on Sen2Cor processor",
+            "name": "SNW",
+            "openeo:gsd": {"value": [20, 20], "unit": "m"},
+        },
+        {
+            "description": "Cloud probability, based on Sen2Cor processor",
+            "name": "CLD",
+            "openeo:gsd": {"value": [20, 20], "unit": "m"},
+        },
+        {
+            "description": "Cloud probability, based on s2cloudless",
+            "name": "CLP",
+            "openeo:gsd": {"value": [160, 160], "unit": "m"},
+        },
+        {"description": "Cloud masks", "name": "CLM", "openeo:gsd": {"value": [160, 160], "unit": "m"}},
+        {
+            "description": "Sun azimuth angle",
+            "name": "sunAzimuthAngles",
+            "openeo:gsd": {"value": [5000, 5000], "unit": "m"},
+        },
+        {
+            "description": "Sun zenith angle",
+            "name": "sunZenithAngles",
+            "openeo:gsd": {"value": [5000, 5000], "unit": "m"},
+        },
+        {
+            "description": "Viewing azimuth angle",
+            "name": "viewAzimuthMean",
+            "openeo:gsd": {"value": [5000, 5000], "unit": "m"},
+        },
+        {
+            "description": "Viewing zenith angle",
+            "name": "viewZenithMean",
+            "openeo:gsd": {"value": [5000, 5000], "unit": "m"},
+        },
+        {"description": "The mask of data/no data pixels.", "name": "dataMask"},
+    ]
+}
diff --git a/tests/integration_tests/test_integration.py b/tests/integration_tests/test_integration.py
index fcfc07e..c2be441 100644
--- a/tests/integration_tests/test_integration.py
+++ b/tests/integration_tests/test_integration.py
@@ -274,7 +274,7 @@ def test_list_supported_processes():
 
 @pytest.mark.parametrize(
     "new_bands",
-    [["B01", "B02", "B03"]],
+    [[{"datasource": "node_loadcollection", "bands": ["B01", "B02", "B03"]}]],
 )
 def test_set_input_bands(new_bands):
     process_graph = get_process_graph_json("bands_null_graph")
@@ -282,7 +282,7 @@ def test_set_input_bands(new_bands):
     result = convert_from_process_graph(process_graph, bands_dimension_name=bands_dimension_name, encode_result=False)
     evalscript = result[0]["evalscript"]
 
-    assert evalscript.input_bands is None
+    assert evalscript.input_bands[0]["bands"] is None
     assert (
         evalscript._output_dimensions[0]["name"] == bands_dimension_name
         and evalscript._output_dimensions[0]["size"] == 0
@@ -297,7 +297,7 @@ def test_set_input_bands(new_bands):
     assert evalscript.input_bands == new_bands
     assert evalscript._output_dimensions[0]["name"] == bands_dimension_name and evalscript._output_dimensions[0][
         "size"
-    ] == len(new_bands)
+    ] == len(new_bands[0]["bands"])
 
     input_object = get_evalscript_input_object(evalscript.write())
     assert input_object["input"] == new_bands
diff --git a/tests/process_graphs/bands_null_graph.json b/tests/process_graphs/bands_null_graph.json
index 060cde1..0467bcc 100644
--- a/tests/process_graphs/bands_null_graph.json
+++ b/tests/process_graphs/bands_null_graph.json
@@ -1,5 +1,5 @@
 {
-   "loadco1":{
+   "loadcollection":{
       "process_id":"load_collection",
       "arguments":{
          "id":"S2L1C",
diff --git a/tests/process_graphs/test_graph_1.json b/tests/process_graphs/test_graph_1.json
index d87cda2..29e038d 100644
--- a/tests/process_graphs/test_graph_1.json
+++ b/tests/process_graphs/test_graph_1.json
@@ -1,5 +1,5 @@
 {
-   "1":{
+   "loadcollection":{
       "process_id":"load_collection",
       "arguments":{
          "id":"BYOC",
@@ -23,7 +23,7 @@
       "process_id":"reduce_dimension",
       "arguments":{
          "data":{
-            "from_node":"1"
+            "from_node":"loadcollection"
          },
          "dimension":"t",
          "reducer":{
diff --git a/tests/process_graphs/test_mean_ndvi.json b/tests/process_graphs/test_mean_ndvi.json
index fa4483d..1d25e28 100644
--- a/tests/process_graphs/test_mean_ndvi.json
+++ b/tests/process_graphs/test_mean_ndvi.json
@@ -1,5 +1,5 @@
 {
-  "1": {
+  "loadcollection": {
     "process_id": "load_collection",
     "arguments": {
       "bands": [
@@ -56,7 +56,7 @@
     "process_id": "reduce_dimension",
     "arguments": {
       "data": {
-        "from_node": "1"
+        "from_node": "loadcollection"
       },
       "reducer": {
         "process_graph": {
diff --git a/tests/process_graphs/test_ndvi_s2l2a.json b/tests/process_graphs/test_ndvi_s2l2a.json
index 2324779..9663a9c 100644
--- a/tests/process_graphs/test_ndvi_s2l2a.json
+++ b/tests/process_graphs/test_ndvi_s2l2a.json
@@ -1,5 +1,5 @@
 {
-   "1":{
+   "loadcollection":{
       "process_id":"load_collection",
       "arguments":{
          "id":"SENTINEL2_L2A_SENTINELHUB",
@@ -33,7 +33,7 @@
       "process_id":"ndvi",
       "arguments":{
          "data":{
-            "from_node":"1"
+            "from_node":"loadcollection"
          },
          "target_band":"NDVI",
          "nir":"B08",
diff --git a/tests/process_graphs/test_resample_cube_temporal_downsample.json b/tests/process_graphs/test_resample_cube_temporal_downsample.json
index 5a0f1dc..38d733f 100644
--- a/tests/process_graphs/test_resample_cube_temporal_downsample.json
+++ b/tests/process_graphs/test_resample_cube_temporal_downsample.json
@@ -1,5 +1,5 @@
 {
-  "loadco1": {
+  "loadcollection": {
     "process_id": "load_collection",
     "arguments": {
       "id": "S2L1C",
@@ -22,7 +22,7 @@
     "process_id": "apply_dimension",
     "arguments": {
       "data": {
-        "from_node": "loadco1"
+        "from_node": "loadcollection"
       },
       "process": {
         "process_graph": {
@@ -80,7 +80,7 @@
     "process_id": "resample_cube_temporal",
     "arguments": {
       "data": {
-        "from_node": "loadco1"
+        "from_node": "loadcollection"
       },
       "target": {
         "from_node": "rename_labels1"
diff --git a/tests/process_graphs/test_resample_cube_temporal_upsample.json b/tests/process_graphs/test_resample_cube_temporal_upsample.json
index 167302b..a65fa8d 100644
--- a/tests/process_graphs/test_resample_cube_temporal_upsample.json
+++ b/tests/process_graphs/test_resample_cube_temporal_upsample.json
@@ -1,5 +1,5 @@
 {
-  "loadco1": {
+  "loadcollection": {
     "process_id": "load_collection",
     "arguments": {
       "id": "S2L1C",
@@ -22,7 +22,7 @@
     "process_id": "apply_dimension",
     "arguments": {
       "data": {
-        "from_node": "loadco1"
+        "from_node": "loadcollection"
       },
       "process": {
         "process_graph": {
@@ -83,7 +83,7 @@
         "from_node": "rename_labels1"
       },
       "target": {
-        "from_node": "loadco1"
+        "from_node": "loadcollection"
       },
       "valid_within": 7
     }