diff --git a/nanshe/io/xjson.py b/nanshe/io/xjson.py
index 4414f070..1bf33421 100644
--- a/nanshe/io/xjson.py
+++ b/nanshe/io/xjson.py
@@ -109,8 +109,7 @@ def ascii_encode_list(data, json_dict=json_dict):
                 new_each_value = ascii_encode_dict(new_each_value)
             elif isinstance(new_each_value, list):
                 new_each_value = ascii_encode_list(new_each_value)
-            elif isinstance(new_each_value, unicode) or \
-                    isinstance(new_each_value, str):
+            elif isinstance(new_each_value, (bytes, unicode)):
                 new_each_value = ascii_encode_str(new_each_value)
 
             if new_each_value is not None:
diff --git a/nanshe/io/xtiff.py b/nanshe/io/xtiff.py
index 30186127..97d1a0e9 100644
--- a/nanshe/io/xtiff.py
+++ b/nanshe/io/xtiff.py
@@ -389,7 +389,7 @@ def convert_tiffs(new_tiff_filenames,
     )))
 
     # if it is only a single str, make it a singleton list
-    if isinstance(new_tiff_filenames, str):
+    if isinstance(new_tiff_filenames, (bytes, unicode)):
         new_tiff_filenames = [new_tiff_filenames]
 
     # Expand any regex in path names