________________________________

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        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     ||

A visual vocabulary is probably analogous to a grammatical vocabulary, in that you develop it by exposing yourself to others' use (and occasional misuse) of it.

IOW, more visits to the art gallery! :D And I find astronomy picture of the day occasionally delightful.

just keep looking at stuff like flickr. or... think about how your dad loves taking pictures and maybe try to associate stories with pictures in order to provide context. :)