diff --git a/src/gui/imgview.py b/src/gui/imgview.py
--- a/src/gui/imgview.py
+++ b/src/gui/imgview.py
@@ -83,5 +83,8 @@ class ImgView(ResizableCanvas):
 		self.create_line(x-3,y+3,x+4,y-4,fill="#00ff00")
 
 	def _onResize(self,event):
+		w=self._width
 		super()._onResize(event)
+		self._corners.scale(self._width/w)
+		self._boardGrid=Grid(self._corners.corners)
 		self.redraw()