diff --git a/src/microcosm/__init__.py b/src/microcosm/__init__.py
index d9d2643..30997dd 100644
--- a/src/microcosm/__init__.py
+++ b/src/microcosm/__init__.py
@@ -345,7 +345,10 @@ def process_multipart_post():
                     frontmatter["thumbnail"] = photo_url
 
                 if "mp-photo-alt[]" in request.form:
-                    alt = request.form["mp-photo-alt[]"][i]
+                    try:
+                        alt = request.form["mp-photo-alt[]"][i]
+                    except:
+                        alt = ""
                 else:
                     alt = ""