I'm a big believer in not buying lenses until you know what you need (for digital or film).
That said, I think the classic trifecta of a 28, a 50 and a telephoto (either a 135 or a 70-210 zoom) will cover nearly everything, I don't go much for long lenses, but I always shot with a 28 and a 50, and still do -- and, funnily enough, the EXIF data for my APS-C digicam shows that I usually shoot around 18, 35 or 55 (max legth on that lens) -- in other words, 28, 50 and telephoto.
I would respectfully disagree with the advice to go for an 85mm lens -- they're expensive (especially if you want a fast one and especially if you shoot Nikon). I would only get one if you shoot a lot of portraiture -- for a general-use telephoto, a 135/2.8 will be a good starting place. Your F can use pre-AI lenses, which are a LOT less expensive than other Nikkor glass -- I say take advantage of that. Looks like pre-AI 135/2.8s are a steal -- wish that was the case with Pentax-M lenses!
HTH
Aaron
That said, I think the classic trifecta of a 28, a 50 and a telephoto (either a 135 or a 70-210 zoom) will cover nearly everything, I don't go much for long lenses, but I always shot with a 28 and a 50, and still do -- and, funnily enough, the EXIF data for my APS-C digicam shows that I usually shoot around 18, 35 or 55 (max legth on that lens) -- in other words, 28, 50 and telephoto.
I would respectfully disagree with the advice to go for an 85mm lens -- they're expensive (especially if you want a fast one and especially if you shoot Nikon). I would only get one if you shoot a lot of portraiture -- for a general-use telephoto, a 135/2.8 will be a good starting place. Your F can use pre-AI lenses, which are a LOT less expensive than other Nikkor glass -- I say take advantage of that. Looks like pre-AI 135/2.8s are a steal -- wish that was the case with Pentax-M lenses!

HTH
Aaron

