This is a lens test made with the new Tokina ATX 124 Pro - 12-24/F4.
This shows the variation in field deepth at F4 and F22.
The Tokina ATX 124 is a serious outperformer for Nikons 12-24 Nikkor DX lens.
Tests made with both lenses gave a serious advantage to the Tokina which is the first lens of that brand made for DX Digital chips only. Not to forget the price which is less than the half of what Nikon charges for it's 12-24.