diff --git a/volume.cc b/volume.cc
index 7bb1c0319d7fb24549afd5714833c8b867baadbb..1a52a8b5a7d2e9f558ef1f0d0ec47bb8b2a6fff2 100644
--- a/volume.cc
+++ b/volume.cc
@@ -129,7 +129,7 @@ namespace MISCMATHS {
        
     float fmin, fmax;
     const ColumnVector& outputvol = *this;
-    FSLIO* OP = FslOpen(fname.c_str(), "wc");
+    FSLIO* OP = FslOpen(fname.c_str(), "wb");
 
     FslSetDim(OP,volinfo.x, volinfo.y, volinfo.z, 1);
     FslSetVoxDim(OP,volinfo.vx, volinfo.vy, volinfo.vz, 0);
@@ -169,7 +169,7 @@ namespace MISCMATHS {
     int fmin, fmax;
 
     const ColumnVector& outputvol = *this;
-    FSLIO* OP = FslOpen(fname.c_str(), "wc");
+    FSLIO* OP = FslOpen(fname.c_str(), "wb");
  
     FslSetDim(OP, volinfo.x, volinfo.y, volinfo.z, 1);  
     FslSetVoxDim(OP, volinfo.vx, volinfo.vy, volinfo.vz, 0);  
@@ -205,7 +205,7 @@ namespace MISCMATHS {
   {
     Time_Tracer ts(string("Volume::read" + fname).c_str());
       
-    FSLIO* IP = FslOpen(fname.c_str(), "r");
+    FSLIO* IP = FslOpen(fname.c_str(), "rb");
     ColumnVector& output = *this;
        
     short x,y,z,v,type;
diff --git a/volumeseries.cc b/volumeseries.cc
index 8e2a7552ecf2bde3b25c1b058b8076b5af8b4a06..6fe72a9955cd5d97db7731592c665b8f7a290a52 100644
--- a/volumeseries.cc
+++ b/volumeseries.cc
@@ -134,7 +134,7 @@ namespace MISCMATHS {
     {
       Time_Tracer ts(string("VolumeSeries::read-" + fname).c_str());
 
-      FSLIO* IP = FslOpen(fname.c_str(), "r");
+      FSLIO* IP = FslOpen(fname.c_str(), "rb");
       Matrix& output = *this;
 
       short x,y,z,v,type;
@@ -231,7 +231,7 @@ namespace MISCMATHS {
     {
        Time_Tracer ts(string("VolumeSeries::writeAsFloat" + fname).c_str());
 
-       FSLIO* OP = FslOpen(fname.c_str(), "wc");
+       FSLIO* OP = FslOpen(fname.c_str(), "wb");
 
        FslSetDim(OP,volinfo.x, volinfo.y, volinfo.z, volinfo.v);
        FslSetVoxDim(OP,volinfo.vx, volinfo.vy, volinfo.vz, volinfo.tr);