diff --git a/.config/zsh/functions/photoprep b/.config/zsh/functions/photoprep
index 4f51e15..85ef360 100755
--- a/.config/zsh/functions/photoprep
+++ b/.config/zsh/functions/photoprep
@@ -6,7 +6,7 @@ setopt LOCAL_OPTIONS ERR_RETURN NO_UNSET PIPE_FAIL
 zmodload zsh/zutil
 local -a o_quality=(-q 90)
 local -a o_size=(-s 1500x1500)
-local -a o_format=(-s webp)
+local -a o_format=(-f webp)
 local -a o_help=()
 zparseopts -D -K -- q:=o_quality s:=o_size f:=o_format h=o_help
 if [[ ${#o_help} -ne 0 || ! -v 1 ]]; then