2 files changed, 9 insertions, 4 deletions
diff --git a/intern/cycles/blender/addon/engine.py b/intern/cycles/blender/addon/engine.py
index 097909ca058..d0f0d395810 100644
--- a/intern/cycles/blender/addon/engine.py
+++ b/intern/cycles/blender/addon/engine.py
@@ -50,11 +50,16 @@ def free(engine):
 
 def render(engine):
     import bcycles
-    bcycles.render(engine.session)
+    if "session" in dir(engine):
+        bcycles.render(engine.session)
 
 def update(engine, data, scene):
     import bcycles
-    bcycles.sync(engine.session)
+    if scene.render.use_border:
+        engine.report({'ERROR'}, "Border rendering not supported yet")
+        free(engine)
+    else:
+        bcycles.sync(engine.session)
 
 def draw(engine, region, v3d, rv3d):
     import bcycles
diff --git a/intern/cycles/blender/addon/properties.py b/intern/cycles/blender/addon/properties.py
index 5a56240865a..bcd3f7d1eac 100644
--- a/intern/cycles/blender/addon/properties.py
+++ b/intern/cycles/blender/addon/properties.py
@@ -108,7 +108,7 @@ class CyclesCameraSettings(bpy.types.PropertyGroup):
 
         cls.aperture_size = FloatProperty(name="Aperture Size", description="Radius of the aperture for depth of field",
             default=0.0, min=0.0, max=10.0)
-        cls.aperture_blades = IntProperty(name="Aperture Blades", description="Number of blades in aperture for polygonal bokeh (need 3 or more)",
+        cls.aperture_blades = IntProperty(name="Aperture Blades", description="Number of blades in aperture for polygonal bokeh (at least 3)",
             default=0, min=0, max=100)
         cls.aperture_rotation = FloatProperty(name="Aperture Rotation", description="Rotation of blades in aperture",
             default=0, soft_min=-math.pi, soft_max=math.pi, subtype='ANGLE')
@@ -121,7 +121,7 @@ class CyclesMaterialSettings(bpy.types.PropertyGroup):
     @classmethod
     def register(cls):
         bpy.types.Material.cycles = PointerProperty(type=cls, name="Cycles Material Settings", description="Cycles material settings")
-        cls.sample_as_light = BoolProperty(name="Sample as Light", description="Use direct light sampling, to reduce noise for small or strong emitting materials", default=True)
+        cls.sample_as_light = BoolProperty(name="Sample as Lamp", description="Use direct light sampling for this material, disabling may reduce overall noise for large objects that emit little light compared to other light sources", default=True)
         cls.homogeneous_volume = BoolProperty(name="Homogeneous Volume", description="When using volume rendering, assume volume has the same density everywhere, for faster rendering", default=False)
 
     @classmethod