Movement in landscapes

 exposure length

Despite what you might first think, the landscape is full of movement - water, clouds, foliage and crops, for example. Movement should ether be captured perfectly frozen or blurred - anything in between can look rressy and unintentional. Which approach you take will depend on the subject, available light, the effect you wish to achieve and oersonal taste. How movement is recorded depends on exposure length: a fast shutter speed freezes movement, while a slow speed blurs it. The exact shutter speed you need depends on the rate and type of movement. As a rule of thumb, a shutter speed upwards of l/250sec will suspend motion while a speed longer than l/4sec begins to blur it. From a practical viewpoint, it is much easier to blur movement, as you ll be typically employing small apertures to maximise depth-of-field and regularly shoot in low light. Also, from an aesthetic point of view, creatively blurring motion is a far more popular technique.

creating ethereal, atmospheric-looking images with implied motion. Water is a popular subject to blur. Rivers, waterfalls and the sea appear very different when shot using a long exposure, with water taking on a smooth, milky appearance. In low light, achieving a long enough exposure to blur motion isnnormally a problem as you ll be using a small aperture and low ISO rating. However, at other times you may need to use a Neutral Density filters to lengthen exposures. An ND filter with a three-stop (0.9ND) strength is useful. Remember, one stop is a halving or doubling of the exposure value. Therefore, if the unfiltered shutter speed is l/8sec, using a three-stop ND slows it to one second. Your camera s metering system automatically adjusts exposures to compensate for a filter s density. Ten-stop N Ds are ideal if you want to exaggerate blurred motion. Don t assume the most striking result will always be achieved by using the longest possible exposure length, though. When using very long exposures,

detail and texture will be lost. Often, a shorter exposure is better, particularly when photographing beach scenes when the tide is gushing around rocks on the shore. By using an exposure in the region of l/2sec, and releasing the shutter just as the water rushes around the foreground rocks, you will capture just enough movement in the water to generate interest and implied motion, while retaining texture and detail in the water. Often, the key is to experiment with different speeds until you achieve just the effect - and level of motion - you desire. A lengthy exposure is also good to blur fast-moving cloud - the effect can look particularly good when the cloud is scudding towards the camera, helping create results with enhanced depth. Crops and vegetation are suitable, too, providing a feeling of motion to otherwise static-looking views. Swaying crops and windblown branches suit exposures around a second or two. Take a sequence of exposures to guarantee the best effect.

Comments are closed.