diff --git a/GammaWorld4e/sheet.json b/GammaWorld4e/sheet.json
index bd60293c11..656a1066ae 100644
--- a/GammaWorld4e/sheet.json
+++ b/GammaWorld4e/sheet.json
@@ -3,7 +3,7 @@
   "css": "gw4sheet.css",
   "authors": "Tyson W",
   "roll20userid": "1130676",
-  "preview": "gw4sheetPreview.png",
+  "preview": "gw4sheetPreview.PNG",
   "instructions": "Character sheet for the Gamma World RPG, 4th edition, by TSR/Wizards of the Coast",
   "legacy": true
 }
\ No newline at end of file