diff --git a/openglcanvas.cpp b/openglcanvas.cpp
index da7b7b4d7fbc3704f7e786887f6a1c322a998c08..a4544c158cad84f10009dc2ff4e7267a2ab219ca 100644
--- a/openglcanvas.cpp
+++ b/openglcanvas.cpp
@@ -27,6 +27,7 @@ OpenGLCanvas::OpenGLCanvas(QWidget *parent) :
 {
     setFormat(QGL::DoubleBuffer | QGL::DepthBuffer);
     fov = 60.f;
+    fov_max = 60.f; // TODO: I only use floats here because Leo did... check
     scale = 1.0f;
     center_lambda = 0.f;
     center_phi = 0.f;
@@ -37,6 +38,8 @@ OpenGLCanvas::OpenGLCanvas(QWidget *parent) :
     time_timer.setInterval(0);
     connect(&time_timer, SIGNAL(timeout()), this, SLOT(slotTimer()));
     time_start = time_time.time();
+
+    fprintf(stderr,"scale=%f\nfov_max=%f\n",scale,fov_max);
 }
 
 void OpenGLCanvas::slotTimer(void) {
@@ -45,23 +48,42 @@ void OpenGLCanvas::slotTimer(void) {
 
 void OpenGLCanvas::change_fov(double f){
 
-    if (fov!=f && f>=1.f && f<=360.f) fov = f;
-    if (fov<60.f) scale = 1.f;
-    else if (fov>295.f) scale = 0.02f;
+    if (fov!=f && f>=1.f && f<=360.f)
+        fov=f;
+    if (fov<=fov_max)
+        scale=1.f;
+    else if (fov>295.f)
+        scale = 0.02f; // TODO: check this value wrt fov_max
     else {
-        if (fov_scale_relation == "Square Root") scale = sqrt((300.f-fov)/240.f);
-        else if (fov_scale_relation == "Linear") scale = (300.f-fov)/240.f;
-        else if (fov_scale_relation == "Square Power") scale = powf((300.f-fov)/240.f,2);
-        else if (fov_scale_relation == "Cubic Power") scale = powf((300.f-fov)/240.f,3);
-        else if (fov_scale_relation == "Logarithm") scale = log(exp(1.f) + (1.f-exp(1.f))*(fov-60.f)/240.f);
+        if (fov_scale_relation == "Naive")
+            scale=fov_max/fov;
+        else if (fov_scale_relation == "Square Root")
+            scale=sqrt((360.f-fov_max-fov)/(360.-2*fov_max));
+        else if (fov_scale_relation == "Linear")
+            scale=(360.f-fov_max-fov)/(360.-2*fov_max);
+        else if (fov_scale_relation == "Square Power")
+            scale=powf((360.f-fov_max-fov)/(360.-2*fov_max),2);
+        else if (fov_scale_relation == "Cubic Power")
+            scale=powf((360.f-fov_max-fov)/(360.-2*fov_max),3);
+        else if (fov_scale_relation == "Logarithm")
+            scale=log(exp(1.f)+(1.f-exp(1.f))*(fov-fov_max)/(360.-2*fov_max));
     }
 
 //    scale = 0.3f;
 
+    fprintf(stderr,"scale=%f\nfov_max=%f\n",scale,fov_max);
+
     updateGL();
 
 }
 
+void OpenGLCanvas::change_fov_max(double new_fov_max){
+    fov_max=new_fov_max;
+    // TODO: change also the scale
+    fprintf(stderr,"scale=%f\nfov_max=%f\n",scale,fov_max);
+    updateGL();
+}
+
 //void OpenGLCanvas::change_scale(double s){
 
 //    if (scale!=s && s>=0.0 && s<=1.0) scale = s;
@@ -93,12 +115,20 @@ void OpenGLCanvas::change_fov_scale_relation(QString name){
    if (fov<60.f) scale = 1.f;
    else if (fov>295.f) scale = 0.01f;
    else{
-       if (fov_scale_relation == "Square Root") scale = sqrt((300.f-fov)/240.f);
-       else if (fov_scale_relation == "Linear") scale = (300.f-fov)/240.f;
-       else if (fov_scale_relation == "Square Power") scale = powf((300.f-fov)/240.f,2);
-       else if (fov_scale_relation == "Cubic Power") scale = powf((300.f-fov)/240.f,3);
-       else if (fov_scale_relation == "Logarithm") scale = log(exp(1.f) + (1.f-exp(1.f))*(fov-60.f)/240.f);
+       if (fov_scale_relation == "Naive")
+           scale=fov_max/fov;
+       else if (fov_scale_relation == "Square Root")
+           scale=sqrt((360.f-fov_max-fov)/(360.-2*fov_max));
+       else if (fov_scale_relation == "Linear")
+           scale=(360.f-fov_max-fov)/(360.-2*fov_max);
+       else if (fov_scale_relation == "Square Power")
+           scale=powf((360.f-fov_max-fov)/(360.-2*fov_max),2);
+       else if (fov_scale_relation == "Cubic Power")
+           scale=powf((360.f-fov_max-fov)/(360.-2*fov_max),3);
+       else if (fov_scale_relation == "Logarithm")
+           scale=log(exp(1.f)+(1.f-exp(1.f))*(fov-fov_max)/(360.-2*fov_max));
    }
+   fprintf(stderr,"scale=%f\nfov_max=%f\n",scale,fov_max);
    updateGL();
 
 }
diff --git a/openglcanvas.h b/openglcanvas.h
index 0ba1f5dbb68e543ed1e3dcb51b2fe6e01c6aa33c..ac854b0461b2b359ddaee4889403a9a231c43a56 100644
--- a/openglcanvas.h
+++ b/openglcanvas.h
@@ -64,6 +64,7 @@ signals:
 
 public slots:
     void change_fov(double f);
+    void change_fov_max(double new_fov_max);
 //    void change_scale(double s);
     void change_center_lambda(double lambda);
     void change_center_phi(double phi);
@@ -74,6 +75,7 @@ public slots:
 
 private:
     double fov;
+    double fov_max; // the \phi_{max} on the technote
     double scale;
     double center_lambda;
     double center_phi;
diff --git a/panowindow1.ui b/panowindow1.ui
index 96a765677db817a13ce0dd225516972a8ee52158..a1f566e2ab7d0d59f8347412fc1fba144d611f64 100644
--- a/panowindow1.ui
+++ b/panowindow1.ui
@@ -37,6 +37,11 @@
        <string>Square Root</string>
       </property>
      </item>
+     <item>
+      <property name="text">
+       <string>Naive</string>
+      </property>
+     </item>
      <item>
       <property name="text">
        <string>Linear</string>