diff --git a/rtgui/curveeditorgroup.cc b/rtgui/curveeditorgroup.cc
index 6e006141a..d0fe49e44 100644
--- a/rtgui/curveeditorgroup.cc
+++ b/rtgui/curveeditorgroup.cc
@@ -277,6 +277,17 @@ void CurveEditorGroup::curveChanged () {
     }
 }
 
+/*
+ * Listener called when the user has modified the curve
+ */
+float CurveEditorGroup::blendPipetteValues (float chan1, float chan2, float chan3) {
+
+	if (cl)
+		return cl->blendPipetteValues(chan1, chan2, chan3);
+
+	return -1.f;
+}
+
 /*
  * Call back method when the reset button is pressed :
  * reset the currently toggled on curve editor
diff --git a/rtgui/curveeditorgroup.h b/rtgui/curveeditorgroup.h
index 182a0ef7a..84a3ec79e 100644
--- a/rtgui/curveeditorgroup.h
+++ b/rtgui/curveeditorgroup.h
@@ -89,6 +89,7 @@ protected:
 	void updateGUI (CurveEditor* ce);
 	void curveResetPressed ();
 	void curveChanged ();
+	float blendPipetteValues(float chan1, float chan2, float chan3);
 	void setUnChanged (bool uc, CurveEditor* ce);
 };
 
diff --git a/rtgui/curvelistener.h b/rtgui/curvelistener.h
index 72980c5d2..c1119703d 100644
--- a/rtgui/curvelistener.h
+++ b/rtgui/curvelistener.h
@@ -23,14 +23,43 @@ class CurveEditor;
 
 class CurveListener {
 
-	private:
-		bool multi;
+    private:
+        bool multi;
     public:
+        CurveListener() : multi(false) {}
+        virtual ~CurveListener() {}
         virtual void curveChanged () {}
         virtual void curveChanged (CurveEditor* ce) {}
         void setMulti(bool value) { multi = value; }
         bool isMulti() { return multi; }
-        CurveListener() : multi(false) {}
+
+        /** @brief Blend pipette values from its different channels into a single value
+        If the buffer has more than one channel and one channel, this method will blend them together.
+        @param chan1 first channel's value
+        @param chan2 second channel's value
+        @param chan3 third channel's value
+        @return the blended value */
+        virtual float blendPipetteValues(float chan1, float chan2, float chan3) {
+            float retVal = 0.f;
+            int n = 0;
+            if (chan1 != -1.f) {
+                retVal += chan1;
+                ++n;
+            }
+            if (chan2 != -1.f) {
+                retVal += chan2;
+                ++n;
+            }
+            if (chan3 != -1.f) {
+                retVal += chan3;
+                ++n;
+            }
+            if (n>1)
+                retVal /= n;
+            else if (!n)
+                retVal = -1.f;
+            return retVal;
+        }
 };
 
 #endif
diff --git a/rtgui/gradient.cc b/rtgui/gradient.cc
index aa4a7cf9c..7d282af94 100644
--- a/rtgui/gradient.cc
+++ b/rtgui/gradient.cc
@@ -40,7 +40,7 @@ Gradient::Gradient () : FoldableToolPanel(this), EditSubscriber(ET_OBJECTS), las
 	centerY->set_tooltip_text (M("TP_GRADIENT_CENTER_Y_TOOLTIP"));
 	centerY->setAdjusterListener (this);
 
-	Gtk::HBox* enaBox = Gtk::manage (new Gtk::HBox());
+	enaBox = Gtk::manage (new Gtk::HBox());
 	enaBox->pack_start(*enabled);
 	enaBox->pack_end(*edit, false, false, 0);
 	pack_start(*enaBox);
@@ -289,6 +289,7 @@ void Gradient::trimValues (rtengine::procparams::ProcParams* pp)
 
 void Gradient::setBatchMode (bool batchMode)
 {
+	removeIfThere(enaBox, edit, false);
 	ToolPanel::setBatchMode (batchMode);
 	degree->showEditedCB ();
 	feather->showEditedCB ();
diff --git a/rtgui/gradient.h b/rtgui/gradient.h
index 0a7b8660a..26c9824bb 100644
--- a/rtgui/gradient.h
+++ b/rtgui/gradient.h
@@ -13,6 +13,7 @@ class Gradient : public ToolParamBlock, public AdjusterListener, public Foldable
 
   private:
     int lastObject;
+    Gtk::HBox* enaBox;
 
   protected:
     Gtk::CheckButton* enabled;
diff --git a/rtgui/mydiagonalcurve.cc b/rtgui/mydiagonalcurve.cc
index 6d4cec7b6..1f04a1f02 100644
--- a/rtgui/mydiagonalcurve.cc
+++ b/rtgui/mydiagonalcurve.cc
@@ -681,25 +681,27 @@ void MyDiagonalCurve::pipetteMouseOver (EditDataProvider *provider, int modifier
 	pipetteG = provider->pipetteVal[1];
 	pipetteB = provider->pipetteVal[2];
 	pipetteVal = 0.f;
-	int n = 0;
-	if (pipetteR != -1.f) {
-		pipetteVal += pipetteR;
-		++n;
+	if (listener)
+		pipetteVal = listener->blendPipetteValues(pipetteR, pipetteG, pipetteB);
+	else {
+		int n = 0;
+		if (pipetteR != -1.f) {
+			pipetteVal += pipetteR;
+			++n;
+		}
+		if (pipetteG != -1.f) {
+			pipetteVal += pipetteG;
+			++n;
+		}
+		if (pipetteB != -1.f) {
+			pipetteVal += pipetteB;
+			++n;
+		}
+		if (n>1)
+			pipetteVal /= n;
+		else if (!n)
+			pipetteVal = -1.f;
 	}
-	if (pipetteG != -1.f) {
-		pipetteVal += pipetteG;
-		++n;
-	}
-	if (pipetteB != -1.f) {
-		pipetteVal += pipetteB;
-		++n;
-	}
-	if (n>1)
-		pipetteVal /= n;
-	else if (!n)
-		pipetteVal = -1.f;
-
-	int num = (int)curve.x.size();
 
 	/* graphW and graphH are the size of the graph */
 	calcDimensions();
@@ -708,7 +710,6 @@ void MyDiagonalCurve::pipetteMouseOver (EditDataProvider *provider, int modifier
 		return;
 
 	double minDistanceX = double(MIN_DISTANCE) / double(graphW-1);
-	double minDistanceY = double(MIN_DISTANCE) / double(graphH-1);
 
 	if (curve.type == DCT_Linear || curve.type == DCT_Spline || curve.type == DCT_NURBS) {
 		// get the pointer position
diff --git a/rtgui/myflatcurve.cc b/rtgui/myflatcurve.cc
index 3a0cbfc2c..23bf72451 100644
--- a/rtgui/myflatcurve.cc
+++ b/rtgui/myflatcurve.cc
@@ -205,8 +205,9 @@ void MyFlatCurve::draw () {
             cr->set_line_width (1.);
         }
     }
+
     // draw the color feedback of the control points
-    else if (colorProvider) {
+    if (colorProvider) {
 
         //if (curve.type!=FCT_Parametric)
             for (int i=0; i<(int)curve.x.size(); ++i) {
@@ -919,23 +920,27 @@ void MyFlatCurve::pipetteMouseOver (EditDataProvider *provider, int modifierKey)
 	pipetteG = provider->pipetteVal[1];
 	pipetteB = provider->pipetteVal[2];
 	pipetteVal = 0.f;
-	int n = 0;
-	if (pipetteR != -1.f) {
-		pipetteVal += pipetteR;
-		++n;
+	if (listener)
+		pipetteVal = listener->blendPipetteValues(pipetteR, pipetteG, pipetteB);
+	else {
+		int n = 0;
+		if (pipetteR != -1.f) {
+			pipetteVal += pipetteR;
+			++n;
+		}
+		if (pipetteG != -1.f) {
+			pipetteVal += pipetteG;
+			++n;
+		}
+		if (pipetteB != -1.f) {
+			pipetteVal += pipetteB;
+			++n;
+		}
+		if (n>1)
+			pipetteVal /= n;
+		else if (!n)
+			pipetteVal = -1.f;
 	}
-	if (pipetteG != -1.f) {
-		pipetteVal += pipetteG;
-		++n;
-	}
-	if (pipetteB != -1.f) {
-		pipetteVal += pipetteB;
-		++n;
-	}
-	if (n>1)
-		pipetteVal /= n;
-	else if (!n)
-		pipetteVal = -1.f;
 
 	snapToElmt = -100;