7Artisans AF 40mm F2.5

Testing found it good across the frame from f/2.5, with slight softness from spherical aberration. Field curvature and focus shift around f/4–f/5.6 mean refocusing is needed for the best corners. Landscapes look best at f/8–f/11. Distortion is low and lateral CA is handled by the in-camera profile. Bokeh is smoother than Sony's 40mm G.

Flare is the clear weakness, with ring flares and large ghosts that stopping down does not fully cure. Vignetting is about 2.8 EV wide open, and autofocus is adequate but neither fast nor quiet. Sony's 40mm G remains sharper and more flare-resistant, at more than three times the price.

Early owners like the tiny size, low price and full set of controls, which make it a natural body-cap lens for travel and street work. Portability is the most consistently praised aspect.

Owner feedback on AF accuracy is mixed, with some reports of hunting, and the AF/MF switch works in the opposite direction to most lenses. Owners still on older bodies such as the original A7 should check 7Artisans' compatibility list.