One of the most exciting ways to portray movement in a photograph is to allow a moving object to become blurred. This approximates the way that our eyes perceive a fast-moving object. To record a moving subject as a blur, you must use your camera’s shutter priority mode to set a slow shutter speed, but the exact slowness depends on several factors, such as the speed of the subject. For example, a Ferris wheel in motion at dusk can be blurred at a shutter speed of at least 1/30 second. Also, a subject passing across your field of view blurs more quickly than one headed straight toward you.