diff --git a/include/osgVolume/VolumeScene b/include/osgVolume/VolumeScene
index 63ad7f26a..117c0bb80 100644
--- a/include/osgVolume/VolumeScene
+++ b/include/osgVolume/VolumeScene
@@ -17,7 +17,8 @@
 #include <osg/Group>
 #include <osg/Texture2D>
 #include <osgUtil/CullVisitor>
-#include <osgVolume/Export>
+
+#include <osgVolume/VolumeTile>
 
 namespace osgVolume {
 
@@ -35,6 +36,8 @@ class OSGVOLUME_EXPORT VolumeScene : public osg::Group
 
         virtual void traverse(osg::NodeVisitor& nv);
 
+        void tileVisited(osg::NodeVisitor* nv, osgVolume::VolumeTile* tile);
+
     protected:
 
         virtual ~VolumeScene();
@@ -48,6 +51,9 @@ class OSGVOLUME_EXPORT VolumeScene : public osg::Group
                 osg::ref_ptr<osg::Camera> _rttCamera;
                 osg::ref_ptr<osg::Camera> _postCamera;
                 osg::ref_ptr<osgUtil::RenderStage> _parentRenderStage;
+
+                typedef std::list< osg::NodePath > Tiles;
+                Tiles _tiles;
             protected:
                 virtual ~ViewData() {}
         };
diff --git a/src/osgVolume/MultipassTechnique.cpp b/src/osgVolume/MultipassTechnique.cpp
index 144932a64..78933b9cf 100644
--- a/src/osgVolume/MultipassTechnique.cpp
+++ b/src/osgVolume/MultipassTechnique.cpp
@@ -13,6 +13,7 @@
 
 #include <osgVolume/MultipassTechnique>
 #include <osgVolume/VolumeTile>
+#include <osgVolume/VolumeScene>
 
 #include <osg/Geometry>
 #include <osg/io_utils>
@@ -77,6 +78,20 @@ void MultipassTechnique::update(osgUtil::UpdateVisitor* /*uv*/)
 void MultipassTechnique::cull(osgUtil::CullVisitor* cv)
 {
     OSG_NOTICE<<"MultipassTechnique::cull() Need to set up"<<std::endl;
+    osg::NodePath& nodePath = cv->getNodePath();
+    for(osg::NodePath::reverse_iterator itr = nodePath.rbegin();
+        itr != nodePath.rend();
+        ++itr)
+    {
+        OSG_NOTICE<<"  parent path node "<<*itr<<" "<<(*itr)->className()<<std::endl;
+        osgVolume::VolumeScene* vs = dynamic_cast<osgVolume::VolumeScene*>(*itr);
+        if (vs)
+        {
+            OSG_NOTICE<<"  HAVE VolumeScene"<<std::endl;
+            vs->tileVisited(cv, getVolumeTile());
+            break;
+        }
+    }
 }
 
 void MultipassTechnique::cleanSceneGraph()
diff --git a/src/osgVolume/VolumeScene.cpp b/src/osgVolume/VolumeScene.cpp
index bfc9d7377..32054471a 100644
--- a/src/osgVolume/VolumeScene.cpp
+++ b/src/osgVolume/VolumeScene.cpp
@@ -14,6 +14,8 @@
 #include <osgVolume/VolumeScene>
 #include <osg/Geometry>
 #include <osg/Geode>
+#include <osg/io_utils>
+#include <osgDB/ReadFile>
 #include <OpenThreads/ScopedLock>
 
 using namespace osgVolume;
@@ -28,7 +30,21 @@ class RTTCameraCullCallback : public osg::NodeCallback
         virtual void operator()(osg::Node* node, osg::NodeVisitor* nv)
         {
 #if 1
+            osgUtil::CullVisitor* cv = dynamic_cast<osgUtil::CullVisitor*>(nv);
+            if (cv)
+            {
+                osg::Camera* camera = cv->getCurrentCamera();
+                OSG_NOTICE<<"Current camera="<<camera<<", node="<<node<<std::endl;
+                OSG_NOTICE<<"  before near ="<<cv->getCalculatedNearPlane()<<std::endl;
+                OSG_NOTICE<<"  before far ="<<cv->getCalculatedFarPlane()<<std::endl;
+            }
+
             _volumeScene->osg::Group::traverse(*nv);
+            if (cv)
+            {
+                OSG_NOTICE<<"  after near ="<<cv->getCalculatedNearPlane()<<std::endl;
+                OSG_NOTICE<<"  after far ="<<cv->getCalculatedFarPlane()<<std::endl;
+            }
 #else
             osg::Group* group = dynamic_cast<osg::Group*>(node);
             if (group)
@@ -70,6 +86,25 @@ VolumeScene::~VolumeScene()
 {
 }
 
+void VolumeScene::tileVisited(osg::NodeVisitor* nv, osgVolume::VolumeTile* tile)
+{
+    osgUtil::CullVisitor* cv = dynamic_cast<osgUtil::CullVisitor*>(nv);
+    if (cv)
+    {
+        osg::ref_ptr<ViewData> viewData;
+
+        {
+            OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_viewDataMapMutex);
+            viewData = _viewDataMap[cv];
+        }
+
+        if (viewData.valid())
+        {
+            OSG_NOTICE<<"tileVisited("<<tile<<")"<<std::endl;
+            viewData->_tiles.push_back(nv->getNodePath());
+        }
+    }
+}
 
 
 void VolumeScene::traverse(osg::NodeVisitor& nv)
@@ -77,9 +112,20 @@ void VolumeScene::traverse(osg::NodeVisitor& nv)
     osgUtil::CullVisitor* cv = dynamic_cast<osgUtil::CullVisitor*>(&nv);
     if (cv)
     {
-        OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_viewDataMapMutex);
-        osg::ref_ptr<ViewData>& viewData = _viewDataMap[cv];
-        if (!viewData)
+        osg::ref_ptr<ViewData> viewData;
+        bool initializeViewData = false;
+        {
+            OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_viewDataMapMutex);
+            if (!_viewDataMap[cv])
+            {
+                _viewDataMap[cv] = new ViewData;
+                initializeViewData = true;
+            }
+
+            viewData = _viewDataMap[cv];
+        }
+
+        if (initializeViewData)
         {
             OSG_NOTICE<<"Creating ViewData"<<std::endl;
 
@@ -87,7 +133,12 @@ void VolumeScene::traverse(osg::NodeVisitor& nv)
             unsigned textureWidth = 512;
             unsigned textureHeight = 512;
 
-            viewData = new ViewData;
+            osg::Viewport* viewport = cv->getCurrentRenderStage()->getViewport();
+            if (viewport)
+            {
+                textureWidth = viewport->width();
+                textureHeight = viewport->height();
+            }
 
             // set up depth texture
             viewData->_depthTexture = new osg::Texture2D;
@@ -109,9 +160,8 @@ void VolumeScene::traverse(osg::NodeVisitor& nv)
             viewData->_colorTexture->setFilter(osg::Texture2D::MIN_FILTER,osg::Texture2D::LINEAR);
             viewData->_colorTexture->setFilter(osg::Texture2D::MAG_FILTER,osg::Texture2D::LINEAR);
 
-            viewData->_colorTexture->setWrap(osg::Texture2D::WRAP_S,osg::Texture2D::CLAMP_TO_BORDER);
-            viewData->_colorTexture->setWrap(osg::Texture2D::WRAP_T,osg::Texture2D::CLAMP_TO_BORDER);
-            viewData->_colorTexture->setBorderColor(osg::Vec4(1.0f,1.0f,1.0f,1.0f));
+            viewData->_colorTexture->setWrap(osg::Texture2D::WRAP_S,osg::Texture2D::CLAMP_TO_EDGE);
+            viewData->_colorTexture->setWrap(osg::Texture2D::WRAP_T,osg::Texture2D::CLAMP_TO_EDGE);
 
 
             // set up the RTT Camera to capture the main scene to a color and depth texture that can be used in post processing
@@ -127,8 +177,6 @@ void VolumeScene::traverse(osg::NodeVisitor& nv)
             // set the camera to render before the main camera.
             viewData->_rttCamera->setRenderOrder(osg::Camera::PRE_RENDER);
 
-            viewData->_rttCamera->setClearColor(osg::Vec4(1.0,0.5,0.5,1.0));
-
             // tell the camera to use OpenGL frame buffer object where supported.
             viewData->_rttCamera->setRenderTargetImplementation(osg::Camera::FRAME_BUFFER_OBJECT);
 
@@ -140,10 +188,45 @@ void VolumeScene::traverse(osg::NodeVisitor& nv)
             // create mesh for rendering the RTT textures onto the screen
             osg::ref_ptr<osg::Geode> geode = new osg::Geode;
             geode->addDrawable(osg::createTexturedQuadGeometry(osg::Vec3(-1.0f,-1.0f,-1.0f),osg::Vec3(2.0f,0.0f,-1.0f),osg::Vec3(0.0f,2.0f,-1.0f)));
-            //geode->getOrCreateStateSet()->setTextureAttributeAndModes(0, viewData->_colorTexture.get(), osg::StateAttribute::ON);
-            geode->getOrCreateStateSet()->setTextureAttributeAndModes(0, viewData->_depthTexture.get(), osg::StateAttribute::ON);
-            geode->getOrCreateStateSet()->setMode(GL_DEPTH_TEST, osg::StateAttribute::OFF);
-            geode->getOrCreateStateSet()->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
+
+            osg::ref_ptr<osg::StateSet> stateset = geode->getOrCreateStateSet();
+
+            stateset->setTextureAttributeAndModes(0, viewData->_colorTexture.get(), osg::StateAttribute::ON);
+            stateset->setTextureAttributeAndModes(1, viewData->_depthTexture.get(), osg::StateAttribute::ON);
+            stateset->setMode(GL_DEPTH_TEST, osg::StateAttribute::OFF);
+            stateset->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
+
+            osg::ref_ptr<osg::Program> program = new osg::Program;
+            stateset->setAttribute(program);
+
+            // get vertex shaders from source
+            osg::ref_ptr<osg::Shader> vertexShader = osgDB::readRefShaderFile(osg::Shader::VERTEX, "shaders/volume_color_depth.vert");
+            if (vertexShader.valid())
+            {
+                program->addShader(vertexShader.get());
+            }
+#if 0
+            else
+            {
+                #include "Shaders/volume_color_depth_vert.cpp"
+                program->addShader(new osg::Shader(osg::Shader::VERTEX, volume_color_depth_vert));
+            }
+#endif
+            // get fragment shaders from source
+            osg::ref_ptr<osg::Shader> fragmentShader = osgDB::readRefShaderFile(osg::Shader::FRAGMENT, "shaders/volume_color_depth.frag");
+            if (fragmentShader.valid())
+            {
+                program->addShader(fragmentShader.get());
+            }
+#if 0
+            else
+            {
+                #include "Shaders/volume_color_depth_frag.cpp"
+                program->addShader(new osg::Shader(osg::Shader::FRAGMENT, volume_color_depth_frag));
+            }
+#endif
+            stateset->addUniform(new osg::Uniform("colorTexture",0));
+            stateset->addUniform(new osg::Uniform("depthTexture",1));
 
             viewData->_postCamera = new osg::Camera;
             viewData->_postCamera->setReferenceFrame(osg::Camera::ABSOLUTE_RF);
@@ -156,11 +239,48 @@ void VolumeScene::traverse(osg::NodeVisitor& nv)
 
         }
 
+        // new frame so need to clear last frames log of VolumeTiles
+        viewData->_tiles.clear();
+
+        // record the parent render stage
         viewData->_parentRenderStage = cv->getCurrentRenderStage();
 
+        osg::Viewport* viewport = cv->getCurrentRenderStage()->getViewport();
+        if (viewport)
+        {
+            if (viewport->width() != viewData->_colorTexture->getTextureWidth() ||
+                viewport->height() != viewData->_colorTexture->getTextureHeight())
+            {
+                OSG_NOTICE<<"Need to change texture size to "<<viewport->width()<<", "<< viewport->height()<<std::endl;
+                viewData->_colorTexture->setTextureSize(viewport->width(), viewport->height());
+                viewData->_colorTexture->dirtyTextureObject();
+                viewData->_depthTexture->setTextureSize(viewport->width(), viewport->height());
+                viewData->_depthTexture->dirtyTextureObject();
+                viewData->_rttCamera->setViewport(0, 0, viewport->width(), viewport->height());
+                viewData->_postCamera->setViewport(0, 0, viewport->width(), viewport->height());
+                if (viewData->_rttCamera->getRenderingCache())
+                {
+                    viewData->_rttCamera->getRenderingCache()->releaseGLObjects(0);
+                }
+            }
+        }
+
+        osg::Camera* parentCamera = cv->getCurrentCamera();
+        viewData->_rttCamera->setClearColor(parentCamera->getClearColor());
+
         OSG_NOTICE<<"Ready to traverse RTT Camera"<<std::endl;
+        OSG_NOTICE<<"   RTT Camera ProjectionMatrix Before "<<viewData->_rttCamera->getProjectionMatrix()<<std::endl;
         viewData->_rttCamera->accept(nv);
 
+        OSG_NOTICE<<"   RTT Camera ProjectionMatrix After "<<viewData->_rttCamera->getProjectionMatrix()<<std::endl;
+        OSG_NOTICE<<"   cv ProjectionMatrix After "<<*(cv->getProjectionMatrix())<<std::endl;
+
+        OSG_NOTICE<<"  after RTT near ="<<cv->getCalculatedNearPlane()<<std::endl;
+        OSG_NOTICE<<"  after RTT far ="<<cv->getCalculatedFarPlane()<<std::endl;
+
+        OSG_NOTICE<<"tileVisited()"<<viewData->_tiles.size()<<std::endl;
+
+
         OSG_NOTICE<<"Ready to traverse POST Camera"<<std::endl;
         viewData->_postCamera->accept(nv);
     }