diff --git a/src/classes/PMusrCanvas.cpp b/src/classes/PMusrCanvas.cpp
index 1982aa4b..2ce52c81 100644
--- a/src/classes/PMusrCanvas.cpp
+++ b/src/classes/PMusrCanvas.cpp
@@ -420,25 +420,27 @@ void PMusrCanvas::SetMsrHandler(PMsrHandler *msrHandler)
       fRRFText = new TString("RRF: ");
       rrfUnitTag = fMsrHandler->GetMsrPlotList()->at(0).fRRFUnit;
       rrfFreq = fMsrHandler->GetMsrPlotList()->at(0).fRRFFreq;
+      TString rrfFreqStr("");
+      rrfFreqStr.Form("%.5g", rrfFreq);
       if (rrfUnitTag == RRF_UNIT_kHz) {
         *fRRFText += TString("#nu_{RRF} = ");
         *fRRFText += rrfFreq;
         *fRRFText += TString(" (kHz)");
       } else if (rrfUnitTag == RRF_UNIT_MHz) {
         *fRRFText += TString("#nu_{RRF} = ");
-        *fRRFText += rrfFreq;
+        *fRRFText += rrfFreqStr;
         *fRRFText += TString(" (MHz)");
       } else if (rrfUnitTag == RRF_UNIT_Mcs) {
         *fRRFText += TString("#omega_{RRF} = ");
-        *fRRFText += rrfFreq;
+        *fRRFText += rrfFreqStr;
         *fRRFText += TString(" (Mc/s)");
       } else if (rrfUnitTag == RRF_UNIT_G) {
         *fRRFText += TString("B_{RRF} = ");
-        *fRRFText += rrfFreq;
+        *fRRFText += rrfFreqStr;
         *fRRFText += TString(" (G)");
       } else if (rrfUnitTag == RRF_UNIT_T) {
         *fRRFText += TString("B_{RRF} = ");
-        *fRRFText += rrfFreq;
+        *fRRFText += rrfFreqStr;
         *fRRFText += TString(" (T)");
       }
       *fRRFText += TString(", RRF packing = ");
@@ -447,25 +449,27 @@ void PMusrCanvas::SetMsrHandler(PMsrHandler *msrHandler)
       fRRFText = new TString("RRF: ");
       rrfUnitTag = fMsrHandler->GetMsrGlobal()->GetRRFUnitTag();
       rrfFreq = fMsrHandler->GetMsrGlobal()->GetRRFFreq(fMsrHandler->GetMsrGlobal()->GetRRFUnit().Data());
+      TString rrfFreqStr("");
+      rrfFreqStr.Form("%.5g", rrfFreq);
       if (rrfUnitTag == RRF_UNIT_kHz) {
         *fRRFText += TString("#nu_{RRF} = ");
-        *fRRFText += rrfFreq;
+        *fRRFText += rrfFreqStr;
         *fRRFText += TString(" (kHz)");
       } else if (rrfUnitTag == RRF_UNIT_MHz) {
         *fRRFText += TString("#nu_{RRF} = ");
-        *fRRFText += rrfFreq;
+        *fRRFText += rrfFreqStr;
         *fRRFText += TString(" (MHz)");
       } else if (rrfUnitTag == RRF_UNIT_Mcs) {
         *fRRFText += TString("#omega_{RRF} = ");
-        *fRRFText += rrfFreq;
+        *fRRFText += rrfFreqStr;
         *fRRFText += TString(" (Mc/s)");
       } else if (rrfUnitTag == RRF_UNIT_G) {
         *fRRFText += TString("B_{RRF} = ");
-        *fRRFText += rrfFreq;
+        *fRRFText += rrfFreqStr;
         *fRRFText += TString(" (G)");
       } else if (rrfUnitTag == RRF_UNIT_T) {
         *fRRFText += TString("B_{RRF} = ");
-        *fRRFText += rrfFreq;
+        *fRRFText += rrfFreqStr;
         *fRRFText += TString(" (T)");
       }
       *fRRFText += TString(", RRF packing = ");
@@ -6156,6 +6160,11 @@ void PMusrCanvas::PlotAverage(Bool_t unzoom)
       break;
   }
 
+  // check if RRF and if yes show a label
+  if ((fRRFText != 0) && (fRRFLatexText != 0)) {
+    fRRFLatexText->DrawLatex(0.1, 0.92, fRRFText->Data());
+  }
+
   fDataTheoryPad->Update();
 
   fMainCanvas->cd();
diff --git a/src/classes/PRunSingleHistoRRF.cpp b/src/classes/PRunSingleHistoRRF.cpp
index e1c4baba..76fef6b4 100644
--- a/src/classes/PRunSingleHistoRRF.cpp
+++ b/src/classes/PRunSingleHistoRRF.cpp
@@ -580,6 +580,12 @@ Bool_t PRunSingleHistoRRF::PrepareFitData(PRawRunData* runData, const UInt_t his
   Double_t freqMax = GetMainFrequency(rawNt);
   cout << "info> freqMax=" << freqMax << " (MHz)" << endl;
 
+  // "optimal packing"
+  Double_t optNoPoints = 8;
+  if (freqMax < 271.0) // < 271 MHz, i.e ~ 2T
+    optNoPoints = 5;
+  cout << "info> optimal packing: " << (Int_t)(1.0 / (fTimeResolution*(freqMax - fMsrInfo->GetMsrGlobal()->GetRRFFreq("MHz"))) / optNoPoints);
+
   // initially fForward is the "raw data set" (i.e. grouped histo and raw runs already added) to be fitted. This means fForward = N(t) at this point.
 
   // 1) check how the background shall be handled
@@ -1108,8 +1114,8 @@ Double_t PRunSingleHistoRRF::GetMainFrequency(PDoubleVector &data)
 Double_t PRunSingleHistoRRF::EstimateN0(Double_t &errN0, Double_t freqMax)
 {
   // endBin is estimated such that the number of full cycles (according to the maximum frequency of the data)
-  // is approximately the time N0EstimateEndTime.
-  Int_t endBin = (Int_t)round(N0EstimateEndTime / fTimeResolution * ceil(freqMax)/freqMax);
+  // is approximately the time fN0EstimateEndTime.
+  Int_t endBin = (Int_t)round(fN0EstimateEndTime / fTimeResolution * ceil(freqMax)/freqMax);
 
   Double_t n0 = 0.0;
   Double_t wN = 0.0;
diff --git a/src/include/PRunSingleHistoRRF.h b/src/include/PRunSingleHistoRRF.h
index fd484bc8..63b063eb 100644
--- a/src/include/PRunSingleHistoRRF.h
+++ b/src/include/PRunSingleHistoRRF.h
@@ -58,7 +58,7 @@ class PRunSingleHistoRRF : public PRunBase
     virtual Bool_t PrepareViewData(PRawRunData* runData, const UInt_t histoNo);
 
   private:
-    static const Double_t N0EstimateEndTime = 1.0; ///< end time in (us) over which N0 is estimated. Should eventually be estimated automatically ...
+    static const Double_t fN0EstimateEndTime = 1.0; ///< end time in (us) over which N0 is estimated. Should eventually be estimated automatically ...
 
     UInt_t fNoOfFitBins;    ///< number of bins to be fitted
     Double_t fBackground;   ///< needed if background range is given (units: 1/bin)