Is the Nikon 12-24mm f/4G AF-S DX Nikkor Lens sharp? This page visually answers that question. Shown above are 100% crops from a lab-captured 18mm f/4.5 test image. Observe the contrast and resolution of these results.
Is the Nikon 12-24mm f/4G AF-S DX Nikkor Lens set to 18mm f/4.5 sharper than the Nikon 16-85mm f/3.5-5.6G AF-S VR DX Nikkor Lens set to 35mm f/4.5? The image quality comparison above also answers that question. Switch between the results to see the sharpness differences between these lenses.