I got a tokina 10-17... seems like I get a lot of curvature with this lens... scott
Fisheye lenses are associated with distortion, always. You have to find a way of using it within the image. In the examples below, the distortion is difficult to see with a circular table coral in the centre of the image, but easy to see in the vertical stalactites which lie to the side of the second image. A wide-angle lens has less distortion, and a lot of that can be taken out in post-processing with Photoshop, Nikon NX etc.
The Nikon 12-24mm has less distortion, but is only happy with some dome ports, and it does need a diopter (I use +2D) which varies from system to system. The example shows little distortion, if any.
The Tokina 10-17mm has a very enthusiastic following, and I guess that you should only buy another lens if you have a very specific task in mind.
Nikon 10.5mm

Nikon 12-24mm

Tim
