This test shows four demonstrative shots from my brickwall testing. These are at f/1.8 (somewhat soft), f/2.2 (pretty sharp), f/8 (sharpest), and f/11 (beginning to soften). Essentially everythink between f/2.2 and f/10 is sharp...f/2 is just a tad softer, as is f/11. These results are true both for this closeup shot, and for more distant shots for which I shot two other series.

The small series are 800pixels on the long side...the large series is at full out-of-camera large size. All were shot NEF 14bit, unaltered, and converted to JPEGS, sRGB, and with conversion sharpening only provided by Photo Mechanic.