diff --git a/README.md b/README.md
index 6897681..e529d54 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,6 @@
+# Careful
+The hyperimage popup requires the presence of the hi-res file prefixed with "orig" as in `imagesCaraffa_1.jpg` and `origimagesCaraffa_1.jpg`.
+
 # Hyperimage insertion
 
 Code was downloaded from