Record timestamp when adding frames to stream

src/openflexure_microscope_server/things/autofocus.py

@@ -345,12 +345,14 @@ class JPEGSharpnessMonitor:
     async def monitor_sharpness(self) -> None:
         """Start monitoring sharpness metrics."""
         self.running = True
-        async for frame in self.camera.lores_mjpeg_stream.frame_async_generator():
-            self._jpeg_times.append(time.time())
+        while self.running:
+            i = await self.camera.lores_mjpeg_stream.next_frame()
+            entry = await self.camera.lores_mjpeg_stream.ringbuffer_entry(i)
+            self._jpeg_times.append(entry.timestamp.timestamp())
 
             # JPEG sharpness metric
             if self.record & SharpnessMethod.JPEG:
-                self._jpeg_sizes.append(len(frame))
+                self._jpeg_sizes.append(len(entry.frame))
 
             # FocusFoM metric
             if self.record & SharpnessMethod.FOCUS_FOM: