diff --git a/scripts/gray_visual.py b/scripts/gray_visual.py
index 8604271..3145762 100644
--- a/scripts/gray_visual.py
+++ b/scripts/gray_visual.py
@@ -25,7 +25,7 @@ def cli_args() -> argparse.Namespace:
                              '(containing gray.ini)')
     parser.add_argument('outputs', type=Path,
                         help='filepath of the outputs directory')
-    parser.add_argument('--kind', '-k', default='raytracing', nargs='+',
+    parser.add_argument('--kind', '-k', default=['raytracing'], nargs='+',
                         choices=['raytracing', 'beam', 'profiles', 'inputs'],
                         help='which kind of information to visualise')
     parser.add_argument('--outfile', '-o',