I had been wanting to buy a couple of lenses, mainly for portrait and another one for landscape. I use a Nikon D5000 and only have a lens AF-S DX Zoom-NIKKOR 18-55mm f/3.5-5.6G ED II First of all, a question. What is the difference between AF-S NIKKOR 50mm f/1.4G and AF NIKKOR 50mm f/1.4D. They are mainly for portraits right? Hence, another question, would my AF-S DX Zoom-NIKKOR 18-55mm f/3.5-5.6G ED II be suffice for portrait purposes? Other than those mentioned what would folks here recommend for a portrait lens? Would a prime lens or soom lens be better? Lastly, I havn't the chance to take landscape pictures. But I figured it's what I would love to do, so I would like to invest in a lens. I hope folks here could help me, because I don't really know what to go for other than what I need might be a wide angle lens. Thanks in advance! Edit= Pricing wise, I wouldn't want to spend 4 digit US$ on a lens.