Quote (CitizenScuba @ Nov 11 2010 06:40pm)
Macro is pretty much always shot focusing manually. Even with AF lenses, it gets to a point where you pinpoint your focus manually, either by using a focusing ring or doing the whole rocking back and forth thing. Seriously, I would go cheap and get a used mf macro lens, then spend what you'd save on a prime to shoot your horses with Marie. You'd be much happier shooting your horses with a sharper, faster, non macro lens anyway. I really think you need to consider this option.
You'll be getting a Canon brand lens likely, so anything you get is auto pro. Nevertheless, a macro lens is 100% fun.