I'm thinking of getting a prime lens as a gift for my son who has a D7000 who will use the lens primarily to photograph his new baby. is there much of a difference in the angle of view between a 30mm and 35mm. The choice seems to be between the Nikon 35mm 1.8 and the Sigma 1.4. The Nikkor seems to be going for about $200 and the newer version of the Sigma about $500. The $300 price differential is pushing me towards the Nikkor. Other than price and the slightly wider view is there any reason to consider the Sigma 1.4. The slight lens speed advantage I don't think enters into my equation. Thanks in advance for any advice or thoughts.