diff --git a/pycromanager/acquisition/acquisition_superclass.py b/pycromanager/acquisition/acquisition_superclass.py
index 42a408bd..8c523c5d 100644
--- a/pycromanager/acquisition/acquisition_superclass.py
+++ b/pycromanager/acquisition/acquisition_superclass.py
@@ -38,9 +38,9 @@ def clear(self):
     def put(self, item: Union[Dict, Generator[Dict, None, None]], block=True, timeout=None):
         if isinstance(item, dict):
             super().put(item, block, timeout)
-        if isinstance(item, list):
+        elif isinstance(item, list):
             super().put(item, block, timeout)
-        # if isinstance(item, tuple):
+        # elif isinstance(item, tuple):
         #     super().put(item, block, timeout)
         elif isinstance(item, Generator):
             super().put(item, block, timeout)
diff --git a/pycromanager/test/test_callback_functions.py b/pycromanager/test/test_callback_functions.py
index 36182582..142d424f 100644
--- a/pycromanager/test/test_callback_functions.py
+++ b/pycromanager/test/test_callback_functions.py
@@ -42,7 +42,7 @@ def hook_fn(image, metadata):
         acq.acquire(events)
         dataset = acq.get_dataset()  # Can this be moved out of the Acquisition context?
 
-    assert dataset is None
+    assert len(dataset.get_index_keys()) == 0
 
 
 def test_img_process_fn_image_saved_fn_consistency(launch_mm_headless, setup_data_folder):