diff --git a/cplusplus/VImage.cc b/cplusplus/VImage.cc
index a09971c9..8ef35d96 100644
--- a/cplusplus/VImage.cc
+++ b/cplusplus/VImage.cc
@@ -37,8 +37,9 @@
 #include <vips/debug.h>
 
 /*
-#define DEBUG
  */
+#define VIPS_DEBUG
+#define DEBUG
 
 VIPS_NAMESPACE_START
 
@@ -62,6 +63,7 @@ VOption *VOption::set( const char *name, const char *value )
 	return( this );
 }
 
+// input int ... this path is used for enums as well
 VOption *VOption::set( const char *name, int value )
 {
 	Pair *pair = new Pair( name );
@@ -74,6 +76,7 @@ VOption *VOption::set( const char *name, int value )
 	return( this );
 }
 
+// input image
 VOption *VOption::set( const char *name, VImage value )
 {
 	Pair *pair = new Pair( name );
@@ -87,6 +90,7 @@ VOption *VOption::set( const char *name, VImage value )
 	return( this );
 }
 
+// output image
 VOption *VOption::set( const char *name, VImage *value )
 {
 	Pair *pair = new Pair( name );
@@ -108,12 +112,14 @@ void VOption::set_operation( VipsOperation *operation )
 
 	for( i = options.begin(); i != options.end(); i++ ) 
 		if( (*i)->input ) {
+#ifdef DEBUG
 			printf( "set_operation: " );
 			vips_object_print_name( VIPS_OBJECT( operation ) );
 			char *str_value = 
 				g_strdup_value_contents( &(*i)->value );
 			printf( ".%s = %s\n", (*i)->name, str_value );
 			g_free( str_value );
+#endif /*DEBUG*/
 
 			g_object_set_property( G_OBJECT( operation ),
 				(*i)->name, &(*i)->value );
@@ -130,12 +136,14 @@ void VOption::get_operation( VipsOperation *operation )
 			g_object_get_property( G_OBJECT( operation ),
 				(*i)->name, &(*i)->value );
 
+#ifdef DEBUG
 			printf( "get_operation: " );
 			vips_object_print_name( VIPS_OBJECT( operation ) );
 			char *str_value = 
 				g_strdup_value_contents( &(*i)->value );
 			printf( ".%s = %s\n", (*i)->name, str_value );
 			g_free( str_value );
+#endif /*DEBUG*/
 
 			// rebox object
 			VipsImage *image = VIPS_IMAGE( 
diff --git a/cplusplus/examples/invert.cc b/cplusplus/examples/invert.cc
index 5eb27b00..2ccb984d 100644
--- a/cplusplus/examples/invert.cc
+++ b/cplusplus/examples/invert.cc
@@ -5,6 +5,8 @@
  *
  */
 
+#define DEBUG
+
 #include <vips/vips8>
 
 using namespace vips8;
@@ -40,7 +42,9 @@ main( int argc, char **argv )
 	printf( "sizeof( VImage ) = %zd\n", sizeof( VImage ) ); 
 
 { 
-	VImage in = VImage::new_from_file( argv[1] ); 
+	VImage in = VImage::new_from_file( argv[1], 
+		VImage::option()->set( "access", VIPS_ACCESS_SEQUENTIAL_UNBUFFERED ) ); 
+
 	VImage out; 
 
 	out = in.invert();
diff --git a/cplusplus/include/vips/VImage8.h b/cplusplus/include/vips/VImage8.h
index b839acf8..fd94213e 100644
--- a/cplusplus/include/vips/VImage8.h
+++ b/cplusplus/include/vips/VImage8.h
@@ -60,6 +60,7 @@ public:
 		g_assert( !new_vobject ||
 			VIPS_IS_OBJECT( new_vobject ) ); 
 
+#ifdef DEBUG
 		printf( "VObject constructor, obj = %p, steal = %d\n",
 			new_vobject, steal ); 
 		if( new_vobject ) { 
@@ -67,8 +68,12 @@ public:
 			vips_object_print_name( VIPS_OBJECT( new_vobject ) );
 			printf( "\n" ); 
 		}
+#endif /*DEBUG*/
+
 		if( !steal ) {
+#ifdef DEBUG
 			printf( "   reffing object\n" ); 
+#endif /*DEBUG*/
 			g_object_ref( vobject ); 
 		}
 	}
@@ -84,10 +89,12 @@ public:
 	{
 		g_assert( VIPS_IS_OBJECT( a.vobject ) ); 
 
+#ifdef DEBUG
 		printf( "VObject copy constructor, obj = %p\n", 
 			vobject ); 
-		g_object_ref( vobject );
 		printf( "   reffing object\n" ); 
+#endif /*DEBUG*/
+		g_object_ref( vobject );
 	}
 
 	// assignment ... we must delete the old ref
@@ -96,9 +103,11 @@ public:
 	{
 		VipsObject *old_vobject;
 
+#ifdef DEBUG
 		printf( "VObject assignment\n" );  
 		printf( "   reffing %p\n", a.vobject ); 
 		printf( "   unreffing %p\n", vobject ); 
+#endif /*DEBUG*/
 
 		g_assert( !vobject ||
 			VIPS_IS_OBJECT( vobject ) ); 
@@ -120,8 +129,10 @@ public:
 	// no vtable allowed
 	~VObject()
 	{
+#ifdef DEBUG
 		printf( "VObject destructor\n" );  
 		printf( "   unreffing %p\n", vobject ); 
+#endif /*DEBUG*/
 
 		g_assert( !vobject ||
 			VIPS_IS_OBJECT( vobject ) );