Update image links from "link" to "file"

Hello!
I want to update all image links in articles. Currently they are linked to their attachment pages, I want to link them directly to the file to use a lightbox-style plugin.

I found this code. It sets image links to “none” – that is nearly what I want, I want them to be set to “file” – is that possible?

This is the “remove”-code:

add_filter( 'the_content', 'attachment_image_link_remove_filter' );
function attachment_image_link_remove_filter( $content ) {
 $content =
 preg_replace(
 array('{<a(.*?)(wp-att|wp-content/uploads)[^>]*><img}',
 '{ wp-image-[0-9]*" /></a>}'),
 array('<img','" />'),
 $content
 );
 return $content;
 }

Thank you very much for your answer!