Our users have been complaining about this as well. I have installed a bookmark into their links toolbar with the following target url as a quick solution until F1 does something. Simple to use, just load an indiviual and as long as they have a picture displayed in your menu bar on the left (as your active person), this bookmark will launch a new window with the full sized version of that picture. Not sure if the forums here are going to mess with my javascript but all of this should be on one line as the URL of the bookmark.
BLOCKED SCRIPTvar mywin = window.open(document.getElementById('ctl00_mgActivePerson').src.substr(0,document.getElementById('ctl00_mgActivePerson').src.length - 1) + 'L','picWindow')