Testing the Sigma 18-35mm f/1.8 Against Nikon's f/1.8 Primes
Last year Sigma made history when they released an 18-35mm zoom with a wicked-fast f/1.8 aperture. Up until then, the fastest wide-to-normal zoom you could get for your crop-sensor camera was something in the neighborhood of a 17-55mm f/2.8 (more than a full stop slower than the current offering from Sigma).