Ok so I'm in looking for a zoom lens to shoot my son's baseball games. Last week I said I didn't want to go over $400.00 but after reading what some of you had to say I decided to go after either the Canon 70-200 f/4L or 70-300 f/4-5.6 IS. Now if I go with the f/4L am I going to need a tripod? And if I go with the f/4-5.6 IS how much image quality am I giving up vs the f/4L? What would all of you get and why? Please help me make up my mind. BTW I am having a great time shooting with my new 30D.