The Nikon 18-35mm G is an exceptionally sharp lens, especially when mounted on a DX camera body where any corner problems are invisible by the smaller sensor. In this case the lens is essentially tack-sharp from corner to corner at any focal length and aperture setting wider than its diffraction limit of ƒ/16. The only exception to this would be at the longer focal length of 35mm, where the corners become very slightly soft at ƒ/11. Stopped down smaller than ƒ/16, we note some slightly generalized softness across the frame.
The full-frame, 36-megapixel sensor of the D800e reveals a bit more of the lens' true nature. The corners of the lens are significantly soft, especially when used wide open. Stopping down the lens helps to slightly alleviate this softness, but there is no combination of settings which provides tack-sharp results from corner to corner. The best results are obtained when the lens is stopped down once (for example, at 18mm, from ƒ/3.5 to ƒ/4; at 24mm, from ƒ/4 to ƒ/5.6). Diffraction limiting is noticeable at ƒ/16, and images are distinctly soft when the lens is fully stopped-down.