diff --git a/pyqtgraph/imageview/ImageView.py b/pyqtgraph/imageview/ImageView.py
index f0c13a60..cb72241a 100644
--- a/pyqtgraph/imageview/ImageView.py
+++ b/pyqtgraph/imageview/ImageView.py
@@ -209,7 +209,7 @@ class ImageView(QtGui.QWidget):
         
         *pos*          Change the position of the displayed image
         *scale*        Change the scale of the displayed image
-        *transform*    Set the transform of the dispalyed image. This option overrides *pos*
+        *transform*    Set the transform of the displayed image. This option overrides *pos*
                        and *scale*.
         ============== =======================================================================
         """
@@ -271,8 +271,9 @@ class ImageView(QtGui.QWidget):
         if levels is None and autoLevels:
             self.autoLevels()
         if levels is not None:  ## this does nothing since getProcessedImage sets these values again.
-            self.levelMax = levels[1]
-            self.levelMin = levels[0]
+            #self.levelMax = levels[1]
+            #self.levelMin = levels[0]
+            self.setLevels(*levels)
             
         if self.ui.roiBtn.isChecked():
             self.roiChanged()
diff --git a/pyqtgraph/parametertree/ParameterItem.py b/pyqtgraph/parametertree/ParameterItem.py
index 376e900d..46499fd3 100644
--- a/pyqtgraph/parametertree/ParameterItem.py
+++ b/pyqtgraph/parametertree/ParameterItem.py
@@ -157,3 +157,9 @@ class ParameterItem(QtGui.QTreeWidgetItem):
         ## since destroying the menu in mid-action will cause a crash.
         QtCore.QTimer.singleShot(0, self.param.remove)
 
+    ## for python 3 support, we need to redefine hash and eq methods.
+    def __hash__(self):
+        return id(self)
+
+    def __eq__(self, x):
+        return x is self
diff --git a/pyqtgraph/widgets/SpinBox.py b/pyqtgraph/widgets/SpinBox.py
index 71695f4a..57e4f1ed 100644
--- a/pyqtgraph/widgets/SpinBox.py
+++ b/pyqtgraph/widgets/SpinBox.py
@@ -313,7 +313,7 @@ class SpinBox(QtGui.QAbstractSpinBox):
         s = [D(-1), D(1)][n >= 0]  ## determine sign of step
         val = self.val
         
-        for i in range(abs(n)):
+        for i in range(int(abs(n))):
             
             if self.opts['log']:
                 raise Exception("Log mode no longer supported.")