What lens should I upgrade to?

I will be going to New York this summer and I only have one lens. The 35mm 1.4. I Thought of getting the Nikon 17-55mm, I use the Nikon D5100. Please help. Thanks.

Added (1). More Night Pictures Or Portrait.

What are you intending to photograph?

that would determine the lens(es) to use…

a tamron 10-24mm for "city scape" shots?
an 18-55mm
a 24-70mm f/2.8
a 50mm f/1.4
an 18-270mm for all round lens to cover most things…

[edit - night pictures and portrait doesn't really narrow things down… What kind of night shots… And what kind of portraits?]

The kit lens (17-55mm in your case, 18-55mm for Canon) is a good learning lens. It is wide enough for nice group and landscape shots and can serve as a portrait lens.

It's not a particularly fast lens(very small maximum aperture) and the more zoomed in you are, the smaller the max aperture gets but that shouldn;t be a mjor issue for someone starting photography.

If you have some money to burn, you could replace that lens with a 24-70 f2.8 (1000$ (Sigma) to 1800$ (Nikon.

The 24-70 on your cropped sensor is a bit tight for landscape shots (36 to 105 equivalent field of view) but it's fast, quality glass… Even the Sigma version has gotten decent reviews.