Sharp Photos Quiz – Test Your Photography Knowledge

Camera shake transfers vibration from the photographer's hands into the camera during the exposure, causing the entire image to blur in the direction of movement. Even small amounts of movement at slow shutter speeds produce visible softness across the whole frame.

The classic rule is a shutter speed of at least 1 over the effective focal length, such as 1/50 second for a 50mm lens or 1/300 second for 200mm on a 1.5x crop body. Longer lenses magnify shake, so one fixed speed such as 1/60 second cannot suit every lens.

Effective focal length is the real focal length multiplied by the crop factor: 200mm times 1.5 equals 300mm. That is the angle of view the lens gives on that sensor, and it magnifies shake to the same degree, so the handheld rule calls for about 1/300 second. Dividing instead of multiplying gives the wrong figure of 133mm.

Breathing moves the chest and shoulders, and the camera moves with them. Exhaling halfway and pressing the shutter in the natural pause that follows keeps you steady, without the tension and trembling that build up when you hold a deep breath.

Image stabilization systems sense rotational movement and apply an equal and opposite correction to an optical element or the sensor. Compensating for the equivalent of three to five stops of shutter speed means a photographer can shoot handheld at speeds that would otherwise produce visible camera shake.

Image stabilization compensates for camera shake but cannot freeze subject movement. Treating it as a tool that extends the range of workable shutter speeds, rather than a substitute for correct technique, uses it appropriately. Turning it off on a tripod prevents the system from introducing micro-corrections to a camera that is already stationary.

The 1 over focal length rule marks the speed where shake is only just controlled. On high-resolution sensors, small movements still show when you zoom in, so shooting two to three times faster than that minimum gives consistently sharp results. Ten times faster is rarely needed.

The lens is the heaviest part of the camera-lens system, and its weight should be supported directly rather than hanging from a grip on the camera body. A hand cradling the bottom of the lens creates a stable platform and reduces the lever-arm effect that makes a heavy lens difficult to hold steadily.