diff --git a/README.md b/README.md
index 59b2b5c..124f514 100644
--- a/README.md
+++ b/README.md
@@ -375,7 +375,7 @@ python scripts/benchmark.py \
   -d eth3d \ # (default) benchmark dataset
   -m minimal \ # overlap level [/leq5/leq10/leq30/all]
   -s facade \ # scene [/courtyard/electro/...]
-  --testset_id 0 \ # id of an ovelrap level (in this case minimal)
+  --testset_id 0 # id of an ovelrap level (in this case minimal)
 ```
 
 
diff --git a/mpsfm/test/simple.py b/mpsfm/test/simple.py
index 2dde109..3c71a11 100644
--- a/mpsfm/test/simple.py
+++ b/mpsfm/test/simple.py
@@ -23,6 +23,8 @@ def __call__(
         images_dir=None,
     ):
         data_dir = Path(data_dir)
+        cache_dir = Path(cache_dir) if cache_dir is not None else None
+        images_dir = Path(images_dir) if images_dir is not None else None
 
         scene_parser = SimpleParser(
             data_dir=data_dir,