diff --git a/modules/ustk_core/src/io/usRawFileParser.cpp b/modules/ustk_core/src/io/usRawFileParser.cpp
index 02407303..0ee2c911 100644
--- a/modules/ustk_core/src/io/usRawFileParser.cpp
+++ b/modules/ustk_core/src/io/usRawFileParser.cpp
@@ -49,13 +49,7 @@
 void usRawFileParser::read(usImage3D<unsigned char> &image3D, const std::string &rawFilename)
 {
   std::ifstream fileStream(rawFilename.c_str(), std::ios::in | std::ios::binary);
-  unsigned int i = 0;
-  while (i < image3D.getSize()) {
-    char c;
-    fileStream.get(c);
-    image3D.getData()[i] = c;
-    i++;
-  }
+  fileStream.read((char *)image3D.getData(), image3D.getSize()*sizeof(unsigned char));
   fileStream.close();
 }
 
@@ -67,11 +61,7 @@ void usRawFileParser::read(usImage3D<unsigned char> &image3D, const std::string
 void usRawFileParser::write(const usImage3D<unsigned char> &image3D, const std::string &rawFilename)
 {
   std::fstream fileStream(rawFilename.c_str(), std::ios::out | std::ios::binary);
-  unsigned int i = 0;
-  while (i < image3D.getSize()) {
-    fileStream.put(image3D.getConstData()[i]);
-    i++;
-  }
+  fileStream.write((const char*)image3D.getConstData(), image3D.getSize()*sizeof(unsigned char));
   fileStream.close();
 }
 
@@ -83,11 +73,7 @@ void usRawFileParser::write(const usImage3D<unsigned char> &image3D, const std::
 void usRawFileParser::read(usImageRF3D<short> &image3D, const std::string &rawFilename)
 {
   std::ifstream fileStream(rawFilename.c_str(), std::ios::in | std::ios::binary);
-  unsigned int i = 0;
-  while (i < image3D.getSize()) {
-    fileStream.read((char *)(image3D.bitmap + i), sizeof(short));
-    i++;
-  }
+  fileStream.read((char*)image3D.bitmap, image3D.getSize()*sizeof(short));
   fileStream.close();
 }
 
@@ -99,11 +85,7 @@ void usRawFileParser::read(usImageRF3D<short> &image3D, const std::string &rawFi
 void usRawFileParser::write(const usImageRF3D<short> &image3D, const std::string &rawFilename)
 {
   std::fstream fileStream(rawFilename.c_str(), std::ios::out | std::ios::binary);
-  unsigned int i = 0;
-  while (i < image3D.getSize()) {
-    fileStream.write((char *)(image3D.getConstData() + i), sizeof(short));
-    i++;
-  }
+  fileStream.write((const char*)image3D.getConstData(), image3D.getSize()*sizeof(short));
   fileStream.close();
 }
 
diff --git a/modules/ustk_grabber/src/usNetworkGrabberPreScan3D.cpp b/modules/ustk_grabber/src/usNetworkGrabberPreScan3D.cpp
index 9c593b8c..2badcc4b 100644
--- a/modules/ustk_grabber/src/usNetworkGrabberPreScan3D.cpp
+++ b/modules/ustk_grabber/src/usNetworkGrabberPreScan3D.cpp
@@ -187,14 +187,9 @@ void usNetworkGrabberPreScan3D::dataArrived()
     m_motorSettings.setMotorRadius(m_imageHeader.motorRadius);
 
     // set data info
-    m_grabbedImage.setFrameCount(m_imageHeader.frameCount);
+    m_grabbedImage.setFrameCount(m_imageHeader.frameCount>1?(m_imageHeader.frameCount-1):0);
     m_grabbedImage.setFramesPerVolume(m_imageHeader.framesPerVolume);
 
-    // warning if timestamps are close (< 10 ms)
-    if (m_imageHeader.timeStamp - m_grabbedImage.getTimeStamp() < 10) {
-      std::cout << "WARNING : new image received with an acquisition timestamp close to previous image (<10ms)"
-                << std::endl;
-    }
     m_grabbedImage.setTimeStamp(m_imageHeader.timeStamp);
 
     m_grabbedImage.resize(m_imageHeader.frameWidth, m_imageHeader.frameHeight);