diff --git a/app/SubWindowHandle.h b/app/SubWindowHandle.h
index fa42088..2c2c76d 100644
--- a/app/SubWindowHandle.h
+++ b/app/SubWindowHandle.h
@@ -66,7 +66,7 @@ public:
    * Scale the image (zoomed in or out) to fit on the window.
    */
   virtual Void zoomToFit() = 0;
-  /*
+  /**
    * Scale the image (zoomed in or out) to speficied absolute zoom value (1.0 = original size).
    */
   virtual Void zoomToFactor( Double factor , QPoint center = QPoint() ) = 0;
@@ -96,8 +96,15 @@ protected:
   QSize getScrollSize();
 
 Q_SIGNALS:
+  /**
+   * Notify that zoom factor was changed by internal event (e.g. by mouse wheel)
+   */
   void zoomFactorChanged_SWindow( const double, const QPoint );
+  /**
+   * Notify that scrollbar position was changed by internal event (e.g. by mouse panning )
+   */
   void scrollBarMoved_SWindow( const QPoint );
+
   void updateStatusBar( const QString& );
 
 public Q_SLOTS:
diff --git a/app/VideoSubWindow.cpp b/app/VideoSubWindow.cpp
index 1e378ad..7cfc642 100644
--- a/app/VideoSubWindow.cpp
+++ b/app/VideoSubWindow.cpp
@@ -83,8 +83,8 @@ VideoSubWindow::VideoSubWindow( QWidget * parent, Bool isModule ) :
 
   // Create a new interface to show images
   m_cViewArea = new ViewArea( this );
-  connect( m_cViewArea, SIGNAL( zoomFactorChanged( double , QPoint) ), this, SLOT( adjustScrollBarByScale( double, QPoint ) ) );
-  connect( m_cViewArea, SIGNAL( zoomFactorChanged( double , QPoint) ), this, SIGNAL( zoomFactorChanged_SWindow( double, QPoint ) ) );
+  connect( m_cViewArea, SIGNAL( zoomFactorChanged_byWheel( double , QPoint) ), this, SLOT( adjustScrollBarByScale( double, QPoint ) ) );
+  connect( m_cViewArea, SIGNAL( zoomFactorChanged_byWheel( double , QPoint) ), this, SIGNAL( zoomFactorChanged_SWindow( double, QPoint ) ) );
 
   connect( m_cViewArea, SIGNAL( scrollBarMoved( QPoint ) ), this, SLOT( adjustScrollBarByOffset( QPoint ) ) );
   connect( m_cViewArea, SIGNAL( scrollBarMoved( QPoint ) ), this, SIGNAL( scrollBarMoved_SWindow( QPoint ) ) );
@@ -346,8 +346,9 @@ Void VideoSubWindow::normalSize()
   Double curFactor = getScaleFactor() ;
   if( factor != curFactor )
   {
-    m_cViewArea->scaleZoomFactor( factor/curFactor, QPoint() );
-    adjustScrollBarByScale( factor/curFactor, QPoint() );
+    Double usedScale;
+    usedScale = m_cViewArea->scaleZoomFactor( factor/curFactor, QPoint() );
+    adjustScrollBarByScale( usedScale, QPoint() );
   }
 }
 
@@ -363,8 +364,9 @@ Void VideoSubWindow::zoomToFactor( Double factor , QPoint center )
   curFactor = getScaleFactor() ;
   if( factor != curFactor )
   {
-    m_cViewArea->scaleZoomFactor( factor/curFactor, center );
-    adjustScrollBarByScale( factor/curFactor, center );
+    Double usedScale;
+    usedScale = m_cViewArea->scaleZoomFactor( factor/curFactor, center );
+    adjustScrollBarByScale( usedScale, center );
   }
 }
 
@@ -373,8 +375,9 @@ Void VideoSubWindow::scaleView( Double scale , QPoint center )
   Q_ASSERT( m_cViewArea->image() );
   if(scale!=1.0)
   {
-    m_cViewArea->scaleZoomFactor( scale, center );
-    adjustScrollBarByScale( scale, center );
+    Double usedScale;
+    usedScale = m_cViewArea->scaleZoomFactor( scale, center );
+    adjustScrollBarByScale( usedScale, center );
   }
 }
 
@@ -404,13 +407,12 @@ Void VideoSubWindow::scaleView( const QSize & size, QPoint center )
   Double curFactor = getScaleFactor() ;
   if( factor != curFactor )
   {
-    m_cViewArea->scaleZoomFactor( factor/curFactor, center );
-    adjustScrollBarByScale( factor/curFactor, center );
+    Double usedScale;
+    usedScale = m_cViewArea->scaleZoomFactor( factor/curFactor, center );
+    adjustScrollBarByScale( usedScale, center );
   }
 }
 
-
-
 Void VideoSubWindow::updatePixelValueStatusBar( const QPoint& pos )
 {
   if( m_pcCurrFrame )
diff --git a/app/VideoSubWindow.h b/app/VideoSubWindow.h
index 9674d3e..1c57584 100644
--- a/app/VideoSubWindow.h
+++ b/app/VideoSubWindow.h
@@ -197,7 +197,7 @@ protected:
 
 public Q_SLOTS:
   void updateSelectedArea( QRect area );
-  void updatePixelValueStatusBar( const QPoint& );
+  void updatePixelValueStatusBar( const QPoint& pos );
 };
 
 }  // NAMESPACE
diff --git a/app/ViewArea.cpp b/app/ViewArea.cpp
index b1262c0..d910afd 100644
--- a/app/ViewArea.cpp
+++ b/app/ViewArea.cpp
@@ -109,29 +109,39 @@ Void ViewArea::setZoomFactor( Double f )
   update();
 }
 
-int ViewArea::scaleZoomFactor( Double scale, QPoint center )
+Double ViewArea::scaleZoomFactor( Double scale, QPoint center )
 {
   Double zoomFactor;
   Double maxZoom = 100.0;
   Double minZoom = 0.01;  //( 1.0 / m_pixmap.width() );
+  Double new_scale = 1.0;
 
   if( ( m_zoomFactor == minZoom ) && ( scale < 1 ) )
-    return 1;
+    return new_scale;
 
   if( ( m_zoomFactor == maxZoom ) && ( scale > 1 ) )
-    return 1;
+    return new_scale;
 
   zoomFactor = m_zoomFactor * scale;
+  new_scale = scale;
 
   if( zoomFactor < minZoom )
+  {
     zoomFactor = minZoom;
-
-  if( zoomFactor > maxZoom )
-    zoomFactor = maxZoom;
+    new_scale = zoomFactor/m_zoomFactor;
+  }
+  else
+  {
+    if( zoomFactor > maxZoom )
+    {
+      zoomFactor = maxZoom;
+      new_scale = zoomFactor/m_zoomFactor;
+    }
+  }
 
   setZoomFactor( zoomFactor );
 
-  return 0;
+  return new_scale;
 }
 
 void ViewArea::setMode( ViewMode mode )
@@ -228,6 +238,7 @@ void ViewArea::setSelectedArea( QRect &rect )
   updateRect.adjust( 0, 0, 1, 1 );
   update( updateRect.normalized() );
 }
+
 ////////////////////////////////////////////////////////////////////////////////
 //                            Geometry Updates 
 ////////////////////////////////////////////////////////////////////////////////
@@ -545,6 +556,7 @@ void ViewArea::paintEvent( QPaintEvent *event )
 void ViewArea::wheelEvent( QWheelEvent *event )
 {
   Double scale;
+  Double usedScale;
 
   if( event->modifiers() & Qt::ControlModifier )
   {
@@ -554,8 +566,11 @@ void ViewArea::wheelEvent( QWheelEvent *event )
     else
       scale=0.8;
 
-    if(scaleZoomFactor( scale , event->pos() ) == 0)
-      emit zoomFactorChanged( scale, event->pos() );
+    usedScale = scaleZoomFactor( scale , event->pos() );
+    if( usedScale != 1.0 )
+    {
+      emit zoomFactorChanged_byWheel( usedScale, event->pos() );
+    }
   }
 }
 
diff --git a/app/ViewArea.h b/app/ViewArea.h
index 1e18c55..77f6868 100644
--- a/app/ViewArea.h
+++ b/app/ViewArea.h
@@ -115,8 +115,8 @@ public:
   void setInputStream( PlaYUVerStream *stream );
   PlaYUVerStream* getInputStream();
 
-  // Scale function. Return 0 when scale is performed. Return 1 otherwise
-  int scaleZoomFactor(Double scale, QPoint center);
+  // Scale function. Return used scale value (it may change when it touches the min or max zoom value)
+  Double scaleZoomFactor(Double scale, QPoint center);
 
   void setTool( eTool tool );
 
@@ -126,7 +126,7 @@ Q_SIGNALS:
   void selectionChanged( const QRect &rect );
   void positionChanged( const QPoint &pos );
   void scrollBarMoved( QPoint offset );
-  void zoomFactorChanged( const double factor , const QPoint center);
+  void zoomFactorChanged_byWheel( const double factor , const QPoint center);
 
 public Q_SLOTS:
   void setNormalMode();
diff --git a/app/plaYUVerApp.cpp b/app/plaYUVerApp.cpp
index f08469d..b326780 100644
--- a/app/plaYUVerApp.cpp
+++ b/app/plaYUVerApp.cpp
@@ -420,7 +420,6 @@ Void plaYUVerApp::zoomToFitAll()
 
 Void plaYUVerApp::zoomToFactorAll( const double scale, const QPoint center )
 {
-  qDebug() << scale << center;
   double factor;
   if( m_pcCurrentSubWindow )
     factor = m_pcCurrentSubWindow->getScaleFactor();