How to combine images at different shutter speeds
You’ve probably heard about exposure blending , in which light and dark exposures of a scene are blended together, usually to balance land and sky. But how about shutter blending? For this, rather than blending brightness, we’ll instead blend different-length exposures – one fast, one slow – to create a single image displaying both a split-second moment and a longer stretch of time. In our first shot, the motion of the cyclist has been captured with a single off-camera flash. This required a fast shutter speed, so we used the camera’s maximum sync speed of 1/250 second – fast enough to capture the motion of the cyclist, but too quick to record much detail in the background. For our second shot, we used a longer exposure of 15 seconds to capture more background detail and blur the motion of a passing gritter truck. (The interesting dashes of light are caused by the truck’s flashing beacons.) A tripod is essential when using shutter blending– both for the long exposure, and to