Getting Proper Exposure with a DSLR Camera

It doesn’t take a trained eye to notice when an image is over or underexposed. Just about anyone can see these faux pas. In photography, exposure refers to the amount of light that is captured by a camera. When too much light is let through the lens, it creates an overexposed image that appears washed out. When a image is underexposed, it will appear too dark and its detail will be lost in the shadowed areas. The goal of the photographer is to find just the right amount of light to achieve the proper exposure.

A properly exposed image can be achieved in three ways: changing the aperture, the ISO setting, and the shutter speed. The aperture measures how wide the lens opens when the camera takes a picture and is a large factor in how a picture will turn out. It is measured in numbers called F-stops that determine how wide the lens needs to open for a properly exposed picture. For instance, an F-4 aperture will let more light in than an F-16. When shooting a bright scene, you will need to set your aperture to a high setting for the picture to turn out right.

The ISO setting represents the sensitivity of the image sensor. For instance, a high ISO will be able to capture every droplet of water falling from a waterfall, whereas a low ISO will show the water as a blur. Though the ISO setting will have the least effect on exposure out of the three, in low light, a high ISO is preferable. Still, this setting should be used with caution as the higher the ISO, the grainier your image will become.

The shutter speed affects the amount of time perceived in a image. A long shutter speed will blur any movement, whereas a short shutter speed will take an image with a crisp scene. The shutter also affects the amount of light that is let through the lens making it important for proper exposure. In terms of exposure, a long shutter speed will let more light through the lens than a shorter shutter speed. The longer that the shutter is open, the more shakiness and movement will be in the image. The best way to overcome this is to use a tripod when you are taking video or photos with a long shutter speed.

The key to taking a great video or picture is being able to accurately adjust the settings of your camera to ensure that your image is properly exposed. Though it may take some time to become familiar with the way that the aperture, ISO, and shutter speed affect different settings and lighting conditions, understanding these settings will greatly improve the look and clarity of your images. Unless you are playing with exposure for artistic purposes, these tips will help keep you from unintentionally overexposing or underexposing your images.

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