I have two newish lenses for my Canon Rebel T2i. I am wondering between the two which is better for portraiture? I am leaning towards the 28-300mm in that zooming in I can create a better depth of field with a blurred background. Also, I am going on a trip and wondering if I should take both lenses? It is not a safari, but I think the 28-300mm would be great for zooming and the 15-85mm for landscapes. Also, which of these two lenses and camera settings works best for portraits of children, pets and people in general. Should I also use AI servo for moving objects? Thank you.