Haha, I've actually been doing research on this exact topic... except not exclusive to MAC foundations. There's a thread about foundation on bridal photography which might be useful:
http://www.specktra.net/forum/f188/b...ography-51649/
I hear mixed reviews about MAC foundations for photography, but seems like most people suggest Studio Fix Stick Foundation if you really want MAC.
Generally, you want to avoid anything with SPF or titanium dioxide in it because these reflect light, which results in pale and washed out faces in pictures, especially flash photography.
Some other suggestions were MUFE Face and Body or MUFE HD.
err that thread was from 20006. A lot has changed in foundations and their formulation..... mainly technology. Especially HD products, gel forumulations, etc. In 2009, I think the best for photos are the HD products and some of the transfer resistant foundations with no spf. MAC foundations are, imo, not good for photography. Sorry to the all the MAC lovers
. The best powders for photography are the HD powders and also the traditional powders which take away shine (Kryolan is the best!).