diff --git a/rtengine/FTblockDN.cc b/rtengine/FTblockDN.cc
index 36362ce7a..84544bb95 100644
--- a/rtengine/FTblockDN.cc
+++ b/rtengine/FTblockDN.cc
@@ -237,7 +237,9 @@ namespace rtengine {
 					}
 				
 				//initial impulse denoise
-				impulse_nr (labdn, 50.0f/20.0f);
+				if (dnparams.luma>0.01) {
+					impulse_nr (labdn, MIN(50.0f,dnparams.luma)/20.0f);
+				}
 				
 				int datalen = labdn->W * labdn->H;
 				
@@ -263,7 +265,9 @@ namespace rtengine {
 				//TODO: at this point wavelet coefficients storage can be freed
 				
 				//second impulse denoise
-				impulse_nr (labdn, 50.0f/20.0f);
+				if (dnparams.luma>0.01) {
+					impulse_nr (labdn, MIN(50.0f,dnparams.luma)/20.0f);
+				}				
 				//PF_correct_RT(dst, dst, defringe.radius, defringe.threshold);
 				
 				//wavelet denoised L channel
diff --git a/rtengine/cplx_wavelet_dec.h b/rtengine/cplx_wavelet_dec.h
index cb1a5eba7..0df25fa72 100644
--- a/rtengine/cplx_wavelet_dec.h
+++ b/rtengine/cplx_wavelet_dec.h
@@ -379,15 +379,15 @@ public:
 		
 		//initialize wavelet filters
 		
-		wavfilt_len = Haar_len;
-		wavfilt_offset = Haar_offset;
+		wavfilt_len = Daub4_len;
+		wavfilt_offset = Daub4_offset;
 		wavfilt_anal = new float[2*wavfilt_len];
 		wavfilt_synth = new float[2*wavfilt_len];
 		
 		for (int n=0; n<2; n++) {
 			for (int i=0; i<wavfilt_len; i++) {
-				wavfilt_anal[wavfilt_len*(n)+i]  = Haar_anal[n][i];
-				wavfilt_synth[wavfilt_len*(n)+i] = Haar_anal[n][wavfilt_len-1-i];
+				wavfilt_anal[wavfilt_len*(n)+i]  = Daub4_anal[n][i];
+				wavfilt_synth[wavfilt_len*(n)+i] = Daub4_anal[n][wavfilt_len-1-i];
 				//n=0 lopass, n=1 hipass
 			}
 		}
diff --git a/rtengine/cplx_wavelet_level.h b/rtengine/cplx_wavelet_level.h
index 26d48d7e1..7d1aaa984 100644
--- a/rtengine/cplx_wavelet_level.h
+++ b/rtengine/cplx_wavelet_level.h
@@ -509,8 +509,8 @@ namespace rtengine {
 		for (int j=0; j<m_w; j++) {
 			loadbuffer(src+j, buffer, m_w/*pitch*/, m_h/*srclen*/);//pad a column of data and load it to buffer
 			if (subsamp_out) {
-				//AnalysisFilterSubsamp (buffer, tmpLo+j, tmpHi+j, filterV, filterV+taps, taps, offset, m_w/*output_pitch*/, m_h/*srclen*/);
-				AnalysisFilterSubsampHaar (buffer, tmpLo+j, tmpHi+j, m_w, m_h);
+				AnalysisFilterSubsamp (buffer, tmpLo+j, tmpHi+j, filterV, filterV+taps, taps, offset, m_w/*output_pitch*/, m_h/*srclen*/);
+				//AnalysisFilterSubsampHaar (buffer, tmpLo+j, tmpHi+j, m_w, m_h);
 			} else {
 				//AnalysisFilter (buffer, tmpLo+j, tmpHi+j, filterV, filterV+taps, taps, offset, m_w/*output_pitch*/, m_h/*srclen*/);
 				AnalysisFilterHaar (buffer, tmpLo+j, tmpHi+j, m_w, m_h);
@@ -522,16 +522,16 @@ namespace rtengine {
 		for (int i=0; i<m_h2; i++) {
 			loadbuffer(tmpLo+i*m_w, buffer, 1/*pitch*/, m_w/*srclen*/);//pad a row of data and load it to buffer
 			if (subsamp_out) {
-				//AnalysisFilterSubsamp (buffer, wavcoeffs[0]+i*m_w2, wavcoeffs[1]+i*m_w2, filterH, filterH+taps, taps, offset, 1/*output_pitch*/, m_w/*srclen*/);
-				AnalysisFilterSubsampHaar (buffer, wavcoeffs[0]+i*m_w2, wavcoeffs[1]+i*m_w2, 1, m_w);
+				AnalysisFilterSubsamp (buffer, wavcoeffs[0]+i*m_w2, wavcoeffs[1]+i*m_w2, filterH, filterH+taps, taps, offset, 1/*output_pitch*/, m_w/*srclen*/);
+				//AnalysisFilterSubsampHaar (buffer, wavcoeffs[0]+i*m_w2, wavcoeffs[1]+i*m_w2, 1, m_w);
 			} else {
 				//AnalysisFilter (buffer, wavcoeffs[0]+i*m_w2, wavcoeffs[1]+i*m_w2, filterH, filterH+taps, taps, offset, 1/*output_pitch*/, m_w/*srclen*/);
 				AnalysisFilterHaar (buffer, wavcoeffs[0]+i*m_w2, wavcoeffs[1]+i*m_w2, 1, m_w);
 			}
 			loadbuffer(tmpHi+i*m_w, buffer, 1/*pitch*/, m_w/*srclen*/);
 			if (subsamp_out) {
-				//AnalysisFilterSubsamp (buffer, wavcoeffs[2]+i*m_w2, wavcoeffs[3]+i*m_w2, filterH, filterH+taps, taps, offset, 1/*output_pitch*/, m_w/*srclen*/);
-				AnalysisFilterSubsampHaar (buffer, wavcoeffs[2]+i*m_w2, wavcoeffs[3]+i*m_w2, 1, m_w);
+				AnalysisFilterSubsamp (buffer, wavcoeffs[2]+i*m_w2, wavcoeffs[3]+i*m_w2, filterH, filterH+taps, taps, offset, 1/*output_pitch*/, m_w/*srclen*/);
+				//AnalysisFilterSubsampHaar (buffer, wavcoeffs[2]+i*m_w2, wavcoeffs[3]+i*m_w2, 1, m_w);
 			} else {
 				//AnalysisFilter (buffer, wavcoeffs[2]+i*m_w2, wavcoeffs[3]+i*m_w2, filterH, filterH+taps, taps, offset, 1/*output_pitch*/, m_w/*srclen*/);
 				AnalysisFilterHaar (buffer, wavcoeffs[2]+i*m_w2, wavcoeffs[3]+i*m_w2, 1, m_w);
@@ -565,7 +565,7 @@ namespace rtengine {
 										filterH, filterH+taps, taps, offset, 1/*pitch*/, m_w/*dstlen*/);
 				SynthesisFilterSubsamp (wavcoeffs[2]+i*m_w2, wavcoeffs[3]+i*m_w2, tmpHi+i*m_w, bufferLo, bufferHi,  \
 										filterH, filterH+taps, taps, offset, 1/*pitch*/, m_w/*dstlen*/);
-				//SynthesisFilterSubsampHaar (wavcoeffs[0]+i*m_w2, wavcoeffs[1]+i*m_w2, tmpLo+i*m_w, 1, m_w);
+				//SynthesisFilterSubsampHaar (wavcoeffs[0]+i*m_w2, wavcoeffs[1]+i*m_w2, tmpLo+i*m_w, 1, m_w);//TODO: this is buggy
 				//SynthesisFilterSubsampHaar (wavcoeffs[2]+i*m_w2, wavcoeffs[3]+i*m_w2, tmpHi+i*m_w, 1, m_w);
 			} else {
 				//SynthesisFilter (wavcoeffs[0]+i*m_w2, wavcoeffs[1]+i*m_w2, tmpLo+i*m_w, bufferLo, bufferHi, \