Hi- I have been researching this which seems like FOREVER! I'll just ask here and maybe someone will take pity on me and solve my problem. I am planning to go pro as soon as I know my camera and equipment inside out- I own the Canon 5D Mark II and the lenses I have are the 24-105 and the 50 1.8. I want to do portraits, weddings and I would also like a lens that is FAST and wont blur when I try to take pics of kids outdoors. I am also going to have a studio at home so I am going to learn all about flash and lighting but one thing at a time. Ok, question is 70-200 2.8 IS or 85 1.2??? Should I get the 70-200 and the 85 1.8 (cheaper)? H-E-L-P I can only afford to get one expensive lens and I don't want to make a mistake and choose the wrong one. Thanks for your help!!!