diff --git a/src/openflexure_microscope_server/things/autofocus.py b/src/openflexure_microscope_server/things/autofocus.py
index 00cd7a4d..eebff335 100644
--- a/src/openflexure_microscope_server/things/autofocus.py
+++ b/src/openflexure_microscope_server/things/autofocus.py
@@ -385,13 +385,17 @@ class JPEGSharpnessMonitor:
             )
         return jpeg_heights[np.argmax(jpeg_sizes)]
 
-    def data_dict(self) -> SharpnessDataArrays:
-        """Return the gathered data as a single convenient dictionary."""
+    def data_to_array(self) -> SharpnessDataArrays:
+        """Return the gathered data as SharpnessDataArrays."""
         data = {}
         for k in ["jpeg_times", "jpeg_sizes", "stage_times", "stage_positions"]:
             data[k] = getattr(self, k)
         return SharpnessDataArrays(**data)
 
+    def data_dict(self) -> dict:
+        """Return the gathered data as dict."""
+        return self.data_to_array().model_dump()
+
 
 class AutofocusThing(lt.Thing):
     """The Thing concerned with combinations of z axis movements and the camera.
@@ -432,7 +436,7 @@ class AutofocusThing(lt.Thing):
             # Move to the target position fz (relative move of (peak - current z))
             sharpness_monitor.focus_rel(peak_z - base_z)
             # Return all focus data
-            return sharpness_monitor.data_dict()
+            return sharpness_monitor.data_to_array()
 
     @lt.action
     def z_move_and_measure_sharpness(
@@ -457,7 +461,7 @@ class AutofocusThing(lt.Thing):
                 if move_index > 0 and wait > 0:
                     time.sleep(wait)
                 sharpness_monitor.focus_rel(current_dz)
-            return sharpness_monitor.data_dict()
+            return sharpness_monitor.data_to_array()
 
     @lt.action
     def looping_autofocus(
@@ -836,6 +840,21 @@ class AutofocusThing(lt.Thing):
         final_z = self._stage.position["z"]
         return final_z, z_positions
 
+    @lt.action
+    def measure_settling_time(
+        self, delay: float = 2, dz: int = 800
+    ) -> SharpnessDataArrays:
+        """Make a Z move down then up by dz, then pause for delay while monitoring sharpness.
+
+        This is useful to see how long to wait for the sharpness value to converge
+        """
+        with JPEGSharpnessMonitor(self._stage, self._cam) as sharpness_monitor:
+            sharpness_monitor.focus_rel(-dz)
+            sharpness_monitor.focus_rel(dz)
+            # Sleep for the given delay, continuing to measure frames without moving
+            time.sleep(delay)
+        return sharpness_monitor.data_to_array()
+
 
 class NotAPeakError(lt.exceptions.InvocationError):
     """The data to fit isn't a peak."""
diff --git a/tests/integration_tests/test_actions.py b/tests/integration_tests/test_actions.py
index 5872c518..80ec2573 100644
--- a/tests/integration_tests/test_actions.py
+++ b/tests/integration_tests/test_actions.py
@@ -114,3 +114,51 @@ def test_camera_stage_mapping_calibration(simulation_test_env):
     assert isinstance(csm_matrix, list)
     # Check CSM is as expected to an absolute tolerance of 1e-3
     assert np.allclose(csm_matrix, expected_matrix, atol=1e-3)
+
+
+def test_measure_settling_time(simulation_test_env):
+    """Test measure_settling_time captures data while moving and holding."""
+    autofocus = simulation_test_env.get_thing_client("autofocus")
+    stage = simulation_test_env.get_thing_client("stage")
+
+    start_z = stage.position["z"]
+
+    delay = 1
+    dz = 1000
+
+    data = autofocus.measure_settling_time(delay=delay, dz=dz)
+
+    # Check returned arrays contain data
+    assert len(data["jpeg_times"]) > 0
+    assert len(data["jpeg_sizes"]) > 0
+    assert len(data["stage_times"]) == 4
+    assert len(data["stage_positions"]) == 4
+
+    # Check the stage moved down then back up
+    z_positions = [p["z"] for p in data["stage_positions"]]
+
+    assert z_positions[0] == start_z
+    assert z_positions[1] == start_z - dz
+    assert z_positions[2] == start_z - dz
+    assert z_positions[3] == start_z
+
+    # Check final stage position returned to start
+    assert stage.position["z"] == start_z
+
+    # Check frames continued to be collected after the final move completed
+    final_move_time = data["stage_times"][-1]
+    jpeg_times_after_final_move = [t for t in data["jpeg_times"] if t > final_move_time]
+
+    assert len(jpeg_times_after_final_move) > 0
+
+
+def test_measure_settling_time_hold_duration(simulation_test_env):
+    """Test measure_settling_time continues capturing during hold."""
+    autofocus = simulation_test_env.get_thing_client("autofocus")
+
+    short_data = autofocus.measure_settling_time(delay=0, dz=400)
+    long_data = autofocus.measure_settling_time(delay=1, dz=400)
+
+    # Longer delay should collect more JPEG frames
+    assert len(long_data["jpeg_times"]) > len(short_data["jpeg_times"])
+    assert len(long_data["jpeg_sizes"]) > len(short_data["jpeg_sizes"])
diff --git a/tests/unit_tests/test_stage_measure.py b/tests/unit_tests/test_stage_measure.py
index d4b5c5a8..fad2df21 100644
--- a/tests/unit_tests/test_stage_measure.py
+++ b/tests/unit_tests/test_stage_measure.py
@@ -247,7 +247,7 @@ def test_offset_from(rom_thing, mocker):
 def test_move_and_measure(perform_autofocus, rom_thing, mocker):
     """Test _move_and_measure with and without initial autofocus checking call counts.
 
-    This doesn't test with the repeate autofocus if motion isn't detected
+    This doesn't test with the repeated autofocus if motion isn't detected
     """
     mock_offset_value = {"x": 100, "y": 3}
     mocker.patch.object(rom_thing, "_offset_from", return_value=mock_offset_value)