diff --git a/photobooth/Photobooth.py b/photobooth/Photobooth.py
index f4583c2..3dd2830 100644
--- a/photobooth/Photobooth.py
+++ b/photobooth/Photobooth.py
@@ -279,4 +279,4 @@ class Photobooth:
     def triggerOn(self):
 
         self._lampOn()
-        self._gpioTrigger = lambda : self._send.send(Gui.TriggerState())
+        self._gpioTrigger = lambda : self._send.send(gui.TriggerState())