I am ready to move up from my Canon Digital Rebel Xti. I am starting some semi-professional work mainly doing portrait studio shots and senior pics. Current lenses are: Canon 18-55mm kit lens (rarely used) Canon 50mm/f1.8 Canon 85mm/f1.8 Canon 70-300mm/f 4.5 - 5.6 I am budgeting $1500 for my next purchase and have settled on the Canon 50D (~$1,000 for body). Question is what lens would any of you recommend? I've seen some nice package deals online. One has the EF-S 18-135mm f/3.5-5.6 IS. Another has the EF 28-135mm f/3.5-5.6 IS USM. Another option is to sell my xti and put that money into a lens, possibly bumping me up to the $1800 range for camera and lens. I'm looking to increase clarity and sharpness in my portait work. Any help is appreciated.