diff --git a/cpdctrl_gui/ui/widgets/plot.py b/cpdctrl_gui/ui/widgets/plot.py
index 3b1324a..075299f 100644
--- a/cpdctrl_gui/ui/widgets/plot.py
+++ b/cpdctrl_gui/ui/widgets/plot.py
@@ -6,7 +6,11 @@ class Plot(pg.GraphicsLayoutWidget):
     """
     pyqtgraph plot widget for showing voltage and LED vs time
 
+    To maintain performance, only a fixed number of data points is stored.
+    Whenever this buffer size is reached, half of the data points are removed
+    and some new data points are skipped to maintain a constant interval.
 
+    This means that accuracy is lost when zooming in!
     """
     def __init__(self, max_data_points=1000):
         super().__init__()