macbook pro 10.7.5 fan running fast and hot

Recently (past 2 weeks) my macbook pro (just over 1 yr old) 10.7.5 fan has been running fast and hot. It begins after uploading photo's into iPhoto '11. Sometimes it takes 30 minutes for it to cool down and run at normal speed. Uploads are usually 50 to 200 images. I verified the Activity Monitor CPU % and nothing exceeds 12%.

I did a restart twice this week which seems to be a temporary solution. Any tips to resolve this is appreciated.

Happens when running iPhoto is only app open.