I am fairly new but am really confused with the different types of lenses. I own a Nikon D90 and was asked to do a favor for a friend and shoot their daughters communion. The whole set up will be very similar to a wedding with a church fase, a reception and formal pictures with the daughter and godparents. I would like to know which lenses would be best and please specify exactly what the difference is with these lenses. I am confused because why when I look at a telephoto 70-300mm lense f/3.5 there is a lense that's similar in specifications as the other one but one costs 800-1grand. I have been researching in tons of books and online and they all say buy this specification but i would like to be shown a link so that i can see it and compare. I'm a visual type of guy. thanks.