I know you guys love the 28-75mm F2.8, and I was about to get that, when I noticed the new Tamron 17-50mm...so..... Tamron 17-50mm F/2.8 or 28-75mm F/2.8 for Nikon D70... I'm getting it to shoot a wedding (for fun, not pay!) Should I go for the long-end or wide-end? I'm thinking 17-50mm since stepping towards the subject solves the issue of the long-end... Advice plz.