ABSTRACT
This chapter considers very different approaches to how passing time is shown in images. Slow shutter speeds and longer time exposures can portray the movement of objects through the frame, creating mesmerizing blurs that track the movement of the subject. Exposure times for such effects are – even among professional photographers – largely a case of trial and error or require bracketing (a series of correct, under- and overexposed images) to produce the desired effect. With film, very long exposures cause a breakdown in the linear relationship between exposure time and the amount of light, which can cause unwanted shifts in colour. In the early days of photography, exposures took tens of seconds rather than the fractions of a second. But as the photographic materials improved to become more sensitive to light, it was possible to reduce exposure times dramatically.
