Public Sub ZoomAboutLogicalPoint ( _
    zoomIncrementFactor As Double, _
    zoomCenterLogicalX As Double, _
    zoomCenterLogicalY As Double _
)

Dim instance As MultiScaleImage
Dim zoomIncrementFactor As Double
Dim zoomCenterLogicalX As Double
Dim zoomCenterLogicalY As Double

instance.ZoomAboutLogicalPoint(zoomIncrementFactor, _
    zoomCenterLogicalX, zoomCenterLogicalY)

public void ZoomAboutLogicalPoint(
    double zoomIncrementFactor,
    double zoomCenterLogicalX,
    double zoomCenterLogicalY
)

<MultiScaleImage x:Name="deepZoomObject" Source="source/items.bin" 
 ImageOpenSucceeded="DeepZoomObject_ImageOpenSucceeded"
 MouseEnter="DeepZoomObject_MouseEnter"
 MouseLeave="DeepZoomObject_MouseLeave"/>

private void DeepZoomObject_ImageOpenSucceeded(object sender, RoutedEventArgs e)
{
    // Turn the animations off when the image first loads. This avoids
    // the default behavior of the image initially zooming into view. 
    // However, you will probably want to turn the animations on later
    // so that the user will have animations when they pan and zoom.
    deepZoomObject.UseSprings = false;
}

private void DeepZoomObject_MouseEnter(object sender, MouseEventArgs e)
{
    // If animation springs were turned off, then 
    // turn them back on
    if (deepZoomObject.UseSprings == false)
    {
        deepZoomObject.UseSprings = true;
    }

    // The ZoomAboutLogicalPoint method allows you to zoom and pan
    // in the same step. The first parameter is the zoom (3x) and the
    // third and fourth parameters are the respective x and y coordinates
    // of the logical point to zoom around.
    this.deepZoomObject.ZoomAboutLogicalPoint(3, .5, .5);
}

private void DeepZoomObject_MouseLeave(object sender, MouseEventArgs e)
{
    double zoom = 1;
    zoom = zoom / 3;
    // This time the zoom is reversed (1/3) although the pan 
    // remains the same - zoom back out from the middle.
    this.deepZoomObject.ZoomAboutLogicalPoint(zoom, .5, .5);
}