diff --git a/src/Demos/hangglide/base.cpp b/src/Demos/hangglide/base.cpp
index 38531024e..c390e2549 100644
--- a/src/Demos/hangglide/base.cpp
+++ b/src/Demos/hangglide/base.cpp
@@ -4,6 +4,7 @@
 #include <osg/GeoSet>
 #include <osg/Texture>
 #include <osg/TexEnv>
+#include <osg/Depth>
 #include <osg/StateSet>
 
 #include <osgDB/ReadFile>
@@ -15,7 +16,7 @@ Node *makeBase( void )
     int i, c;
     float theta;
     float ir, ori;
-    ir = 6.0;
+    ir = 0.0;
     ori = 20.0;
 
     Vec3 *coords = new Vec3[38];
@@ -85,6 +86,15 @@ Node *makeBase( void )
         gstate->setAttr( PFSTATE_FOG, fog );
     */
 
+    // clear the depth to the far plane.
+    osg::Depth* depth = new osg::Depth;
+    depth->setFunction(osg::Depth::ALWAYS);
+    depth->setRange(1.0,1.0);   
+    dstate->setAttributeAndModes(depth,StateAttribute::ON );
+
+    dstate->setRenderBinDetails(-1,"RenderBin");
+
+
     gset->setStateSet( dstate );
 
     Geode *geode = new Geode;
diff --git a/src/Demos/hangglide/hangglide.cpp b/src/Demos/hangglide/hangglide.cpp
index 8327ab0c1..7d95c4377 100644
--- a/src/Demos/hangglide/hangglide.cpp
+++ b/src/Demos/hangglide/hangglide.cpp
@@ -1,5 +1,7 @@
 #include <osg/Group>
 #include <osg/Notify>
+#include <osg/Depth>
+#include <osg/StateSet>
 
 #include <osgDB/Registry>
 #include <osgDB/ReadFile>
@@ -123,11 +125,19 @@ int main( int argc, char **argv )
         // no database loaded so automatically create Ed Levin Park..
         osg::Group* group = new osg::Group;
         rootnode = group;
-        group->addChild(makeTerrain());
-        group->addChild(makeTank());
-        group->addChild(makeSky());
-        group->addChild(makeBase());
-        group->addChild(makeTrees());
+        
+        // the base and sky subgraphs go to set the earth sky of the
+        // model and clear the color and depth buffer for us, by using
+        // osg::Depth, and setting their bin numbers to less than 0,
+        // to force them to draw before the rest of the scene.
+        
+        group->addChild(makeSky());  // bin number -2 so drawn first.
+        group->addChild(makeBase()); // bin number -1 so draw second.
+
+        // the rest of the scene drawn after the base and sky above.
+        group->addChild(makeTrees()); // will drop into a transparent, depth sorted bin (1)
+        group->addChild(makeTerrain()); // will drop into default bin - state sorted 0
+        group->addChild(makeTank()); // will drop into default bin - state sorted 0
         // add the following in the future...
         // makeGliders
         // makeClouds
@@ -139,6 +149,22 @@ int main( int argc, char **argv )
     osgGLUT::Viewer viewer;
     viewer.addViewport( rootnode );
 
+
+    osg::StateSet* stateset = rootnode->getStateSet();
+    if (stateset==NULL)
+    {
+        stateset = new osg::StateSet;
+        rootnode->setStateSet(stateset);
+    }
+    
+    // set up depth to be inherited by the rest of the scene unless
+    // overrideen.
+    osg::Depth* rootDepth = new osg::Depth;
+    rootDepth->setFunction(osg::Depth::LESS);
+    rootDepth->setRange(0.0,1.0);
+
+    stateset->setAttributeAndModes(rootDepth, osg::StateAttribute::ON );
+
     unsigned int pos = viewer.registerCameraManipulator(new GliderManipulator());
 
     // Open window so camera manipulator's warp pointer request will succeed
@@ -146,6 +172,12 @@ int main( int argc, char **argv )
 
     viewer.selectCameraManipulator(pos);
 
+    osgUtil::SceneView* sv = viewer.getViewportSceneView(0);
+    
+    // switch off the render stages clear mask as we use the earth/sky
+    // to clear it for us, see above.
+    sv->getRenderStage()->setClearMask(0);
+
     viewer.run();
 
     return 0;
diff --git a/src/Demos/hangglide/sky.cpp b/src/Demos/hangglide/sky.cpp
index 7e285093e..9770b7a5f 100644
--- a/src/Demos/hangglide/sky.cpp
+++ b/src/Demos/hangglide/sky.cpp
@@ -4,6 +4,7 @@
 #include <osg/GeoSet>
 #include <osg/Texture>
 #include <osg/TexEnv>
+#include <osg/Depth>
 #include <osg/StateSet>
 
 #include <osgDB/ReadFile>
@@ -96,6 +97,15 @@ Node *makeSky( void )
     dstate->setAttribute( new TexEnv );
     dstate->setMode( GL_LIGHTING, StateAttribute::OFF );
     dstate->setMode( GL_CULL_FACE, StateAttribute::ON );
+    
+
+    // clear the depth to the far plane.
+    osg::Depth* depth = new osg::Depth;
+    depth->setFunction(osg::Depth::ALWAYS);
+    depth->setRange(1.0,1.0);   
+    dstate->setAttributeAndModes(depth,StateAttribute::ON );
+
+    dstate->setRenderBinDetails(-2,"RenderBin");
 
     gset->setStateSet( dstate );
 
diff --git a/src/Demos/osgreflect/osgreflect.cpp b/src/Demos/osgreflect/osgreflect.cpp
index a2d65afdd..2a0b68937 100644
--- a/src/Demos/osgreflect/osgreflect.cpp
+++ b/src/Demos/osgreflect/osgreflect.cpp
@@ -301,7 +301,8 @@ int main( int argc, char **argv )
     osg::ColorMask* rootColorMask = new osg::ColorMask;
     rootColorMask->setMask(true,true,true,true);        
     
-    // set up depth so all writing to depth goes to maximum depth.
+    // set up depth to be inherited by the rest of the scene unless
+    // overrideen. this is overridden in bin 3.
     osg::Depth* rootDepth = new osg::Depth;
     rootDepth->setFunction(osg::Depth::LESS);
     rootDepth->setRange(0.0,1.0);