diff --git a/rtengine/CA_correct_RT.cc b/rtengine/CA_correct_RT.cc
index cef4e5171..f9b6a6daa 100644
--- a/rtengine/CA_correct_RT.cc
+++ b/rtengine/CA_correct_RT.cc
@@ -153,9 +153,9 @@ void RawImageSource::CA_correct_RT(double cared, double cablue) {
 	//temporary parameters for tile CA evaluation
 	float	gdiff, deltgrb;
 	//interpolated G at edge of plaquette
-	float	Ginthfloor, Ginthceil, Gint, RBint, gradwt;
+	float	Ginthfloor, Ginthceil, Gint, gradwt;
 	//interpolated color difference at edge of plaquette
-	float	grbdiffinthfloor, grbdiffinthceil, grbdiffint, grbdiffold;
+	float	grbdiffint, grbdiffold;
 	//data for evaluation of block CA shift variance
 	float	blockave[2][3]={{0,0,0},{0,0,0}}, blocksqave[2][3]={{0,0,0},{0,0,0}}, blockdenom[2][3]={{0,0,0},{0,0,0}}, blockvar[2][3];
 	//low and high pass 1D filters of G in vertical/horizontal directions
@@ -790,36 +790,21 @@ void RawImageSource::CA_correct_RT(double cared, double cablue) {
 
 					grbdiffold = rgb[indx][1]-rgb[indx][c];
 
-					//interpolate color difference from optical R/B locations to grid locations
-					grbdiffinthfloor=(1-shifthfrac[c]/2)*grbdiff[indx]+(shifthfrac[c]/2)*grbdiff[indx-2*GRBdir[1][c]];
-					grbdiffinthceil=(1-shifthfrac[c]/2)*grbdiff[(rr-2*GRBdir[0][c])*TS+cc]+(shifthfrac[c]/2)*grbdiff[(rr-2*GRBdir[0][c])*TS+cc-2*GRBdir[1][c]];
-					//grbdiffint is bilinear interpolation of G-R/G-B at grid point
-					grbdiffint=(1-shiftvfrac[c]/2)*grbdiffinthfloor+(shiftvfrac[c]/2)*grbdiffinthceil;
+					//gradient weights using difference from G at CA shift points and G at grid points
+					p[0]=1/(eps+fabs(rgb[indx][1]-gshift[indx]));
+					p[1]=1/(eps+fabs(rgb[indx][1]-gshift[indx-2*GRBdir[1][c]]));
+					p[2]=1/(eps+fabs(rgb[indx][1]-gshift[(rr-2*GRBdir[0][c])*TS+cc]));
+					p[3]=1/(eps+fabs(rgb[indx][1]-gshift[(rr-2*GRBdir[0][c])*TS+cc-2*GRBdir[1][c]]));
+					
+					grbdiffint = (p[0]*grbdiff[indx]+p[1]*grbdiff[indx-2*GRBdir[1][c]]+ \
+								  p[2]*grbdiff[(rr-2*GRBdir[0][c])*TS+cc]+p[3]*grbdiff[(rr-2*GRBdir[0][c])*TS+cc-2*GRBdir[1][c]])/(p[0]+p[1]+p[2]+p[3]);
 					
 					//now determine R/B at grid points using interpolated color differences and interpolated G value at grid point
-					RBint=rgb[indx][1]-grbdiffint;
-					
-					if (fabs(RBint-rgb[indx][c])<0.25*(RBint+rgb[indx][c])) {
-						if (fabs(grbdiffold)>fabs(grbdiffint) ) {
-							rgb[indx][c]=RBint;
-						}
-					} else {
-						
-						//gradient weights using difference from G at CA shift points and G at grid points
-						p[0]=1/(eps+fabs(rgb[indx][1]-gshift[indx]));
-						p[1]=1/(eps+fabs(rgb[indx][1]-gshift[indx-2*GRBdir[1][c]]));
-						p[2]=1/(eps+fabs(rgb[indx][1]-gshift[(rr-2*GRBdir[0][c])*TS+cc]));
-						p[3]=1/(eps+fabs(rgb[indx][1]-gshift[(rr-2*GRBdir[0][c])*TS+cc-2*GRBdir[1][c]]));
-						
-						grbdiffint = (p[0]*grbdiff[indx]+p[1]*grbdiff[indx-2*GRBdir[1][c]]+ \
-									  p[2]*grbdiff[(rr-2*GRBdir[0][c])*TS+cc]+p[3]*grbdiff[(rr-2*GRBdir[0][c])*TS+cc-2*GRBdir[1][c]])/(p[0]+p[1]+p[2]+p[3]);
-						
-						//now determine R/B at grid points using interpolated color differences and interpolated G value at grid point
-						if (fabs(grbdiffold)>fabs(grbdiffint) ) {
-							rgb[indx][c]=rgb[indx][1]-grbdiffint;
-						}
+					if (fabs(grbdiffold)>fabs(grbdiffint) ) {
+						rgb[indx][c]=rgb[indx][1]-grbdiffint;
 					}
 					
+					
 					//if color difference interpolation overshot the correction, just desaturate
 					if (grbdiffold*grbdiffint<0) {
 						rgb[indx][c]=rgb[indx][1]-0.5*(grbdiffold+grbdiffint);
diff --git a/rtengine/procparams.cc b/rtengine/procparams.cc
index ea2eefb6f..ed85ff800 100644
--- a/rtengine/procparams.cc
+++ b/rtengine/procparams.cc
@@ -740,8 +740,8 @@ if (keyFile.has_group ("RAW")) {
 	if (keyFile.has_key ("RAW", "DarkFrame"))     raw.dark_frame = keyFile.get_string  ("RAW", "DarkFrame" );
 	if (keyFile.has_key ("RAW", "DarkFrameAuto")) raw.df_autoselect = keyFile.get_boolean ("RAW", "DarkFrameAuto" );
 	if (keyFile.has_key ("RAW", "CA"))            raw.ca_autocorrect = keyFile.get_boolean ("RAW", "CA" );
-	if (keyFile.has_key ("RAW", "CARed"))            raw.cared = keyFile.get_boolean ("RAW", "CARed" );
-	if (keyFile.has_key ("RAW", "CABlue"))            raw.cablue = keyFile.get_boolean ("RAW", "CABlue" );
+	if (keyFile.has_key ("RAW", "CARed"))            raw.cared = keyFile.get_double ("RAW", "CARed" );
+	if (keyFile.has_key ("RAW", "CABlue"))            raw.cablue = keyFile.get_double ("RAW", "CABlue" );
 	if (keyFile.has_key ("RAW", "HotDeadPixels")) raw.hotdeadpix_filt = keyFile.get_boolean ("RAW", "HotDeadPixels" );
 	if (keyFile.has_key ("RAW", "LineDenoise"))   raw.linenoise = keyFile.get_integer ("RAW", "LineDenoise" );
 	if (keyFile.has_key ("RAW", "GreenEqThreshold")) raw.greenthresh= keyFile.get_integer ("RAW", "GreenEqThreshold");