Tracking lightbox images with Google Analytics

Hi,

I manage several sites for artists and use a lightbox plug-in (jQuery lightbox for native galleries) on many of these sites. A common request is to track image views on Google Analytics. Since the lightbox does not trigger a pageview, I have surmised that event tracking is the answer, but I am not sure how to integrate the code. I have read about a Javascript called gatag.js. Does anyone have any experience with this ? A sample page I would like to track image views on is this one of my own works on canvas :
http://colingoldberg.com/artwork/works-on-canvas/

Any input would be greatly appreciated.

Thanks,
Colin