diff --git a/yt/utilities/amr_kdtree/amr_kdtools.py b/yt/utilities/amr_kdtree/amr_kdtools.py
index f42e3a36f7f..01d7327a267 100644
--- a/yt/utilities/amr_kdtree/amr_kdtools.py
+++ b/yt/utilities/amr_kdtree/amr_kdtools.py
@@ -3,13 +3,17 @@
 from yt.funcs import mylog
 
 
-def receive_and_reduce(comm, incoming_rank, image, add_to_front):
+def receive_and_reduce(comm, incoming_rank, image, add_to_front, *, use_opacity=True):
     mylog.debug("Receiving image from %04i", incoming_rank)
     # mylog.debug( '%04i receiving image from %04i'%(self.comm.rank,back.owner))
     arr2 = comm.recv_array(incoming_rank, incoming_rank).reshape(
         (image.shape[0], image.shape[1], image.shape[2])
     )
 
+    if not use_opacity:
+        np.add(image, arr2, image)
+        return image
+
     if add_to_front:
         front = arr2
         back = image
@@ -31,6 +35,7 @@ def receive_and_reduce(comm, incoming_rank, image, add_to_front):
     for i in range(4):
         np.multiply(image[:, :, i], ta, image[:, :, i])
     np.add(image, front, image)
+
     return image
 
 
diff --git a/yt/utilities/amr_kdtree/amr_kdtree.py b/yt/utilities/amr_kdtree/amr_kdtree.py
index b8378c66715..861f4320c14 100644
--- a/yt/utilities/amr_kdtree/amr_kdtree.py
+++ b/yt/utilities/amr_kdtree/amr_kdtree.py
@@ -294,7 +294,7 @@ def get_reduce_owners(self):
                 owners[temp.node_id] = owners[temp.left.node_id]
         return owners
 
-    def reduce_tree_images(self, image, viewpoint):
+    def reduce_tree_images(self, image, viewpoint, *, use_opacity=True):
         if self.comm.size <= 1:
             return image
         myrank = self.comm.rank
@@ -307,7 +307,11 @@ def reduce_tree_images(self, image, viewpoint):
             split_pos = node.parent.get_split_pos()
             add_to_front = viewpoint[split_dim] >= split_pos
             image = receive_and_reduce(
-                self.comm, owners[node.parent.right.node_id], image, add_to_front
+                self.comm,
+                owners[node.parent.right.node_id],
+                image,
+                add_to_front,
+                use_opacity=use_opacity,
             )
             if node.parent.node_id == 1:
                 break
diff --git a/yt/visualization/volume_rendering/render_source.py b/yt/visualization/volume_rendering/render_source.py
index 65d6cd2e557..c7d0beed2e4 100644
--- a/yt/visualization/volume_rendering/render_source.py
+++ b/yt/visualization/volume_rendering/render_source.py
@@ -607,7 +607,11 @@ def render(self, camera, zbuffer=None):
 
     def finalize_image(self, camera, image):
         if self._volume is not None:
-            image = self.volume.reduce_tree_images(image, camera.lens.viewpoint)
+            image = self.volume.reduce_tree_images(
+                image,
+                camera.lens.viewpoint,
+                use_opacity=self.transfer_function.grey_opacity,
+            )
 
         return super().finalize_image(camera, image)