The Tokina AT-X 116 PRO DX is an ultra-wide angle lens with a fast f/2.8 aperture for better photography in low-light situations. It could be the lens you use most often for ship-board photography. Its fast, sharp, and super-wide angle, perfect to capture the interesting subject matter on board.
Overview: I classify this lens as semi-pro, as it has a metal mounting ring, and very well built. So why do I recommend a 3rd party lens over a Nikon-brand lens. Simply, its a better fit for cruise photography. The sharpness of this lens exceeds the Nikkor 10-24, as well as it's superior low-light capability, and the price (which is 25% less). And the lens is argubly better built. Some of Nikon's made-in-China lenses are somewhat suspect. While not a bad lens, the Nikkor 10-24 should look and feel better given it's $800 price tag.
One advantage of the Nikkor is it has a 1mm advantage at the lower end of the zoom, and afterall, you are buying an ultra-wide lens for the wide angle. However, the usefulness of the f2.8 Tokina lens more than makes up for the focal length advantage of the Nikkor in that you will find the Tokina easier to use for interior photos, low light at-night photos of you stuffing your face at the midnight buffet, and so on.
However, the Tokina is AF while the Nikon is AF-S, so if you have a lower end Nikon camera (D3000, D3100, D5000, D40, and so on) it will not be able to autofocus with the Tokina, so this may give the advantage to the Nikkor. In reality though, at these extreme wide angles, most everything is going to be in focus anyway.
There have been some reported issues with earlier Tokina Lenses having problems correctly auto-focusing. While I cannot verify whether or not this is true, the prudent thing to do is to is to purchase it from a high-volume dealer to ensure you are getting newer product, and do not purchase gray market, eBay, or other non-traditional sources. If you purchase via eBay, make sure it is with a reputable dealer that does not sell gray market.
Alternatives: The Sigma has an even wider 8mm offering, and like the Nikkor, their HSM technology consists of essentially an in-lens focusing motor, similar to Nikon's AF-S. Given the similar aperature range, the Sigma might be an attractive lower cost alternative for those needing AF-S focusing. The field-of-view for the Tokina @ 11mm is 104mm, for the Nikkor @ 10mm is 109mm, and the Sigma @ 8mm is 121 deg, which is the widest super-wide angle lens available today.
Tamron also has a 10-24mm f3.5~4.5 lens, however, I find it hard to recommend as I have never thought their lenses to be in the same quality range as the other three. While the Tamron is cheaper, I think you would be happier if you saved a few more dollars and bought the Tokina or Sigma.
10mm - English Harbor and Nelson's Dockyard - Antigua
11mm - English Harbor and Nelson's Dockyard - Antigua
Summary: From the photo above, the difference between 10mm and 11mm is not readily apparent, and in my opinion, not enough to offset the superior optics of the Tokina. Tokina is somewhat of a boutique lens maker these days, and concentrates on making a few great lenses rather than a wide-range of lenses like the camera manufacturers tend to do. In reality, you will likely be happy with any of the lenses reviewed here; but you may be "more-happy" with the one that lightens your wallet the least. The Tokina has a good reputation, and unlike many 3rd-party offerings, should you decide to sell it, it has a decent resale.