diff --git a/octoprint/server.py b/octoprint/server.py
index e60436a..6147706 100644
--- a/octoprint/server.py
+++ b/octoprint/server.py
@@ -287,7 +287,7 @@ def getTimelapseData():
 	elif lapse is not None and isinstance(lapse, timelapse.TimedTimelapse):
 		type = "timed"
 		additionalConfig = {
-			"interval": lapse.interval
+			"interval": lapse.interval()
 		}
 
 	files = timelapse.getFinishedTimelapses()