Question: I’m just getting to grips with my DSLR but can’t really figure out the B mode. What is this for?
Answer: The Bulb mode allows users to set a very slow shutter speed for long exposure photography. In all other modes, the longest available exposure time is usually 30 seconds, but in low light conditions this sometimes isn’t enough to achieve a properly exposed image. In Bulb, you can keep the shutter open for as long as required; for several minutes or even hours. Bulb mode is useful for fireworks, vehicle light trails and astro work. It’s usually used with a remote shutter release, as users would otherwise have to keep a finger pressed on the shutter button for the duration of the exposure, leading to camera shake. A sturdy tripod is also needed to keep the camera perfectly still. When shooting in daylight, a neutral density filter will be necessary in order to achieve very long exposures. On some cameras, Bulb is represented by B on the mode dial, but on others it’s accessed by changing the shutter speed setting to beyond 30 seconds.