Output The Featured Image in a Loop as a Linked Media Image
Instead of linking a featured image to a post permalink in a loop – here is how you can link to its original image of itself.
So above, the title and featured image is output of a post – the title has a link to the post whilst the image is linked to itself via the $large_image_url which uses the first value in the array [0] which is the src value.
Further more a lightbox CSS class name can be triggered so a bunch of featured images can be viewed in an archive loop page without going to the single post page