diff --git a/nansat/vrt.py b/nansat/vrt.py
index 879ae785..5674c82b 100644
--- a/nansat/vrt.py
+++ b/nansat/vrt.py
@@ -371,7 +371,7 @@ def _init_from_array(self, array, **kwargs):
         array_shape = array.shape
         binary_file = self.filename.replace('.vrt', '.raw')
         ofile = gdal.VSIFOpenL(str(binary_file), str('wb'))
-        array_bytes = array.tostring()
+        array_bytes = array.tobytes()
         array = None
         batch_size = 0x20000000 # 512 MB
         for i in range(0,len(array_bytes),batch_size):
diff --git a/setup.py b/setup.py
index 7e437c27..2e0a3563 100644
--- a/setup.py
+++ b/setup.py
@@ -46,7 +46,7 @@
 AUTHOR_EMAIL        = "nansat-dev@googlegroups.com"
 PLATFORMS           = ["Linux", "OS X", "Windows"]
 ISRELEASED          = True
-VERSION             = os.getenv('NANSAT_RELEASE', '0.0.0dev').lstrip('v')
+VERSION             = os.getenv('NANSAT_RELEASE', '1.5.2').lstrip('v')
 REQS                = [
                         "Pillow",
                         "pythesint",