Hello! I’m hoping you can all help me out. I have gotten into wedding photography and currently shoot with a Nikon D90. I’m going to invest in the D7000 (use my D90 as a back-up) and would like to know which lens to purchase. I have: 50mm f/1.8D AF Nikkor Lens 18-105mm f/3.5-5.6 AF-S DX VR ED Nikkor Lens Any advice?? I'm looking to spend <$1,000 for a solid lens. I love the 105mm, however, want to ensure that the next lens I purchase will be the last for quite some time. Thank you in advance!