Hi again, After studying and reading a lot about DSLR's and lenses, I've finally come to conclusion to buy Sigma 10-20mm 1:4-5.6 EX DC HSM for my Nikon D3200. I'm planning a trip to Europe and have a Nikon D3200 with 18-55mm kit lens. I know its great for landscapes but I do not want to be constrained by lens once I reach there since then there would be no option then. Just wanted to know if its the right decision. Also, read somewhere that there is no autofocus and it has to be done from the Camera itself. Need help on this too.