diff --git a/mongoengine/fields.py b/mongoengine/fields.py
index 5b2f14a4..55e5addb 100644
--- a/mongoengine/fields.py
+++ b/mongoengine/fields.py
@@ -505,10 +505,11 @@ class BinaryField(BaseField):
         return pymongo.binary.Binary(value)
 
     def to_python(self, value):
-        return unicode(value)
+        # Returns str not unicode as this is binary data
+        return str(value)
 
     def validate(self, value):
         assert isinstance(value, str)
 
         if self.max_bytes is not None and len(value) > self.max_bytes:
-            raise ValidationError('Binary value is too long')
\ No newline at end of file
+            raise ValidationError('Binary value is too long')
diff --git a/mongoengine/queryset.py b/mongoengine/queryset.py
index 40779ab7..396a745c 100644
--- a/mongoengine/queryset.py
+++ b/mongoengine/queryset.py
@@ -918,7 +918,7 @@ class QuerySetManager(object):
                     opts = {'capped': True, 'size': max_size}
                     if max_documents:
                         opts['max'] = max_documents
-                    self._collection = db.create_collection(collection, opts)
+                    self._collection = db.create_collection(collection, **opts)
             else:
                 self._collection = db[collection]