Tagging individual photos within an article

I want to be able to tag individual photos within articles I post – my web developer is saying this is not possible in WP and that you can only tag the article as a whole?

Another other connected issue – my site content is articles and photos. The developer has set it up so that posts are marked as an article or a photo. Is there a way to set it up so that photos within articles are automatically posted as individual photos (ideally with their tags intact).

Any help would be gratefully appreciated!