diff --git a/rtgui/histogrampanel.cc b/rtgui/histogrampanel.cc
index 8946a5e35..63d299fa5 100644
--- a/rtgui/histogrampanel.cc
+++ b/rtgui/histogrampanel.cc
@@ -497,6 +497,8 @@ void HistogramPanel::type_selected(Gtk::RadioButton* button)
     if (histogramRGBArea) {
         updateHistRGBAreaOptions();
     }
+    histogramArea->setDirty(true);
+    histogramArea->queue_draw();
 }
 
 void HistogramPanel::type_changed()