diff --git a/ApplicationLibCode/UnitTests/CvfCameraCrashTriage-Test.cpp b/ApplicationLibCode/UnitTests/CvfCameraCrashTriage-Test.cpp
index 4de036bfdb..6340d3ef43 100644
--- a/ApplicationLibCode/UnitTests/CvfCameraCrashTriage-Test.cpp
+++ b/ApplicationLibCode/UnitTests/CvfCameraCrashTriage-Test.cpp
@@ -85,3 +85,44 @@ TEST( CvfCameraCrashTriageTest, FitViewWithParallelDirAndUpProducesValidViewMatr
     EXPECT_NEAR( c.direction() * c.right(), 0.0, 1e-6 );
     EXPECT_NEAR( c.up() * c.right(), 0.0, 1e-6 );
 }
+
+//--------------------------------------------------------------------------------------------------
+/// A zero view direction (eye == view reference point, as in caf::Viewer::zoomAll()) gave a zero up
+/// vector and a zero-normal plane, which asserted in Plane::distanceToOrigin().
+//--------------------------------------------------------------------------------------------------
+TEST( CvfCameraCrashTriageTest, FitViewEyePositionWithZeroDirDoesNotCrash )
+{
+    Camera c;
+
+    BoundingBox bb;
+    bb.add( Vec3d( 0, 0, 0 ) );
+    bb.add( Vec3d( 1, 1, 1 ) );
+
+    for ( const auto& dir : { Vec3d::ZERO, Vec3d::UNDEFINED } )
+    {
+        Vec3d eye = Camera::computeFitViewEyePosition( bb, dir, Vec3d( 0, 0, 1 ), 0.9, c.fieldOfViewYDeg(), 1.0 );
+
+        EXPECT_FALSE( eye.isUndefined() );
+    }
+}
+
+//--------------------------------------------------------------------------------------------------
+/// fitView() must derive the up vector from the same valid direction as the eye position
+//--------------------------------------------------------------------------------------------------
+TEST( CvfCameraCrashTriageTest, FitViewWithZeroOrUndefinedDirProducesValidViewMatrix )
+{
+    BoundingBox bb;
+    bb.add( Vec3d( 0, 0, 0 ) );
+    bb.add( Vec3d( 1, 1, 1 ) );
+
+    for ( const auto& dir : { Vec3d::ZERO, Vec3d::UNDEFINED } )
+    {
+        Camera c;
+        c.setViewport( 0, 0, 100, 100 );
+        c.fitView( bb, dir, Vec3d( 0, 0, 1 ), 0.9 );
+
+        EXPECT_NEAR( c.direction().length(), 1.0, 1e-6 );
+        EXPECT_NEAR( c.up().length(), 1.0, 1e-6 );
+        EXPECT_NEAR( c.right().length(), 1.0, 1e-6 );
+    }
+}
diff --git a/Fwk/VizFwk/LibRender/cvfCamera.cpp b/Fwk/VizFwk/LibRender/cvfCamera.cpp
index 698a571b6f..4014502e05 100644
--- a/Fwk/VizFwk/LibRender/cvfCamera.cpp
+++ b/Fwk/VizFwk/LibRender/cvfCamera.cpp
@@ -43,10 +43,23 @@
 #include "cvfBoundingBox.h"
 #include "cvfGeometryUtils.h"
 
+#include <limits>
+
 namespace cvf {
 
 namespace {
 
+//--------------------------------------------------------------------------------------------------
+/// A zero, undefined or non-finite view direction cannot define a view; fall back to looking along the Y axis
+//--------------------------------------------------------------------------------------------------
+Vec3d validViewDirection(const Vec3d& dir)
+{
+    const double length = dir.length();
+    if (!dir.isUndefined() && length > 0.0 && length < std::numeric_limits<double>::max()) return dir;
+
+    return Vec3d::Y_AXIS;
+}
+
 //--------------------------------------------------------------------------------------------------
 /// Returns an up vector guaranteed to be non-parallel to dir. If the passed up vector is already
 /// non-parallel to dir, it is returned unchanged. Otherwise a corrected, orthogonal up vector is
@@ -310,8 +323,10 @@ void Camera::setProjectionAsPixelExact2D()
 /// the view to. The relativeDistance parameter specifies the distance from the camera to the 
 /// center of the bounding box
 //--------------------------------------------------------------------------------------------------
-void Camera::fitView(const BoundingBox& boundingBox, const Vec3d& dir, const Vec3d& up, double coverageFactor)
+void Camera::fitView(const BoundingBox& boundingBox, const Vec3d& dirIn, const Vec3d& up, double coverageFactor)
 {
+    const cvf::Vec3d dir = validViewDirection(dirIn);
+
     // dir and up may be parallel (degenerate camera orientation); derive a corrected, non-parallel
     // up vector so both the eye computation and the final look-at matrix use a consistent basis.
     cvf::Vec3d correctedUp = nonParallelUpVector(dir, up);
@@ -327,8 +342,10 @@ void Camera::fitView(const BoundingBox& boundingBox, const Vec3d& dir, const Vec
 //--------------------------------------------------------------------------------------------------
 /// 
 //--------------------------------------------------------------------------------------------------
-Vec3d Camera::computeFitViewEyePosition(const BoundingBox& boundingBox, const Vec3d& dir, const Vec3d& up, double coverageFactor, double fieldOfViewYDeg, double aspectRatio) 
+Vec3d Camera::computeFitViewEyePosition(const BoundingBox& boundingBox, const Vec3d& dirIn, const Vec3d& up, double coverageFactor, double fieldOfViewYDeg, double aspectRatio) 
 {
+    const cvf::Vec3d dir = validViewDirection(dirIn);
+
     cvf::Vec3d corners[8];
     boundingBox.cornerVertices(corners);