Why f/22 Might Be Ruining Your Sharpest Shots

Every aperture on your lens does a different job, and the wrong one can quietly soften an image you thought was tack sharp. The choice sits at the center of exposure, depth of field, and the entire feel of a photograph, which is why arguments over the "best" aperture never really end.

Working through the dial from f/8 down to f/22, Craig Roberts builds the case for and against each stop before landing on his own preference. Roberts flags f/22 early as the one to avoid, pointing to diffraction, the way light bends around the blades of a narrow aperture and scatters as it passes through the glass elements. Push the lens that far and depth of field climbs while overall sharpness drops, so the gain cancels itself out. He notes this feels more like a digital problem, since shooting film he happily exposed Fuji Velvia 50 with a polarizer at 1/8 second and f/22 on sunny days, back when a loupe on the light table did the judging instead of a 100 percent zoom in Photoshop.

Much of the video sorts out how the same number behaves differently across sensor sizes. f/16 on full frame lands near f/8 on Micro Four Thirds and around f/11 on APS-C, which reframes what "small aperture" even means depending on your camera. Roberts favors f/8 for handheld landscape and urban work, dropping to f/5.6 on dull days and nudging up to f/11 only when a close foreground subject needs to stay sharp. He also revisits the old "f/8 and be there" idea for street shooting: set the aperture, pre-focus to two or three meters, and most of the frame from roughly a meter to infinity holds focus, leaving you free to watch the moment instead of the settings.

The reasoning here connects to a wider shift in how people talk about lens performance. Every lens has a range where it performs at its best, usually a couple of stops down from wide open, and diffraction sets the ceiling on the narrow end. On smaller sensors that ceiling arrives sooner, which is why Micro Four Thirds and APS-C shooters run into softness at apertures that full frame users treat as routine. Understanding the equivalence math gives you a portable rule: pick your sharpness target on one system, then translate it when you switch bodies rather than assuming f/16 means the same thing everywhere. That single principle saves a lot of guesswork when you move between formats or read advice written for a sensor you don't own.

Where Roberts finally lands upends the sharpness-first thinking that dominates most of the discussion. His favorite is the wide end, though he won't pin it to one number, since the widest aperture depends on the lens. On his 35mm f/1.4, he tends to stop down slightly to f/1.8, so that becomes his choice on that glass. On a zoom, f/2.8 might be the widest available and therefore his pick. The point is selective focus: opening up, letting the light flood in, and blurring the foreground or background to steer the viewer's eye exactly where he wants it. He frames all of this with the reminder that depth of field also depends on focal length, using a 35mm lens as the working example throughout.

Give the video above a watch to hear how Roberts talks himself through each stop before revealing the aperture he actually reaches for.