diff --git a/detect.cc b/detect.cc
index 1df7ba5..121de5d 100644
--- a/detect.cc
+++ b/detect.cc
@@ -93,23 +93,11 @@ void Detect::Thread() {
 			LockMutex();					// lock Config
 
 			//
-			// 1. if no position of the object is known, search brightest
-			//    object on the inFrame image.
-			if (objectX < objectW/2 || objectX > (inFrame.w-objectW/2) ||
-				objectY < objectH/2 || objectY > (inFrame.h-objectH/2))
-			{
-				switch (autodetecttype) {
-				case AUTODETECT_BRIGHT:
-					InputDetect(&objectX, &objectY);
-					break;
-				default:
-					break;
-				}
-			}
+			// 1. check near the last known position.
 			//
-			// 2. check near the last known position.
-			//
-			else {
+			if (objectX >= objectW/2 && objectX <= (inFrame.w-objectW/2) &&
+				objectY >= objectH/2 && objectY <= (inFrame.h-objectH/2))
+			{
 				switch (autofollowtype) {
 				case AUTOFOLLOW_BRIGHT:
 					InputDetect(&objectX, &objectY);
@@ -127,6 +115,21 @@ void Detect::Thread() {
 				}
 			}
 
+			//
+			// 2. if no position of the object is known, search brightest
+			//    object on the inFrame image.
+			if (objectX < objectW/2 || objectX > (inFrame.w-objectW/2) ||
+				objectY < objectH/2 || objectY > (inFrame.h-objectH/2))
+			{
+				switch (autodetecttype) {
+				case AUTODETECT_BRIGHT:
+					InputDetect(&objectX, &objectY);
+					break;
+				default:
+					break;
+				}
+			}
+
 			oldFrame.CopyFrom(&inFrame);
 			UnLockInMutex();
 
@@ -225,6 +228,8 @@ void Detect::InputDetect(int *posx, int *posy) {
 			didx = 3* (image.w * dy + dx);
 			for (i = 0; i < 3; i++) pxi[didx+i] = pxs[idx+i];
 		}
+
+	return;
 }
 
 /* returns approx. 8-bit gray value */
@@ -320,6 +325,7 @@ void Detect::InputDetectCrossC(int *posx, int *posy) {
 	*posx += (mxx-DET_MAXSHIFT/2);
 	*posy += (mxy-DET_MAXSHIFT/2);
 	CopyObjectImage (*posx, *posy);
+	return;
 }
 
 
diff --git a/detect.h b/detect.h
index d3f47c3..2b30a53 100644
--- a/detect.h
+++ b/detect.h
@@ -147,6 +147,7 @@ struct  {
 	uint32_t *detmatrix;
 	int posx;			// position of the detected object
 	int posy;			// position of the detected object
+	int valid;			// valid position detected
 } typedef DetectOutput;
 
 
diff --git a/gui.cc b/gui.cc
index af31462..132d807 100644
--- a/gui.cc
+++ b/gui.cc
@@ -56,12 +56,12 @@ void cb_window_show (GtkWidget *widget, gpointer data) {
 	GtkWidget *btnstop = GTK_WIDGET(gtk_builder_get_object (GTK_BUILDER(_builder_), "btn-video-stop"));
 	GtkWidget *w = GTK_WIDGET(gtk_builder_get_object (GTK_BUILDER(_builder_), "detect-entry-w"));
 	GtkWidget *h = GTK_WIDGET(gtk_builder_get_object (GTK_BUILDER(_builder_), "detect-entry-h"));
-	GtkWidget *rboff = GTK_WIDGET(gtk_builder_get_object (GTK_BUILDER(_builder_), "detect-pos-cboff"));
-	GtkWidget *rbcrossc = GTK_WIDGET(gtk_builder_get_object (GTK_BUILDER(_builder_), "detect-type-indet2"));
+	GtkWidget *rbdefdetect = GTK_WIDGET(gtk_builder_get_object (GTK_BUILDER(_builder_), "detect-pos-cbbright"));
+	GtkWidget *rbdeffolow = GTK_WIDGET(gtk_builder_get_object (GTK_BUILDER(_builder_), "detect-type-indet2"));
 
 	// changing the value, will cause the 'change' event to be triggered
-	gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(rboff), true);
-	gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(rbcrossc), true);
+	gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(rbdefdetect), true);
+	gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(rbdeffolow), true);
 
 
 	gtk_widget_set_sensitive(btnstart, true);
diff --git a/simpleskycam.ui b/simpleskycam.ui
index f7fb5bb..bca2a0a 100644
--- a/simpleskycam.ui
+++ b/simpleskycam.ui
@@ -307,7 +307,6 @@
                                 <property name="halign">start</property>
                                 <property name="valign">start</property>
                                 <property name="draw-indicator">True</property>
-                                <property name="group">detect-pos-cbbright</property>
                                 <signal name="toggled" handler="cb_detect_detecttype" swapped="no"/>
                               </object>
                               <packing>