Exposure is the amount of time that a camera’s sensor is exposed to light. Exposure controls how much light reaches the sensor and determines the brightness of the image captured. In general, the longer the shutter speed (the length of time the shutter remains open) the less light reaching the sensor. The shorter the shutter speed, the brighter the image will appear.
The two types of exposure are called aperture-priority and manual. Aperture-priority means the camera automatically selects the best possible combination of f-stop and shutter speed based on the lighting conditions. Manual means the photographer sets both values.
Aperture priority mode is useful if you want to control depth of field. Depth of field refers to the area in front of and behind the subject where objects appear sharp. If you have a shallow depth of field, everything in front of and behind your subject appears sharp. However, if you have a deep depth of field, only things close to your subject appear sharp.
Shutter speed affects motion blur. Motion blur occurs when moving subjects don’t appear sharp. Shorter shutter speeds cause less blurring than longer shutter speeds.
In order to achieve good results, you need to understand what each setting does and how they work together. Here are some tips to help you get started:
• When shooting landscapes, use a wide aperture (small f-number). This lets in lots of light and creates a shallow depth of field.
• Use a tripod to keep your camera steady.
• Set the ISO at 100 or 200. This helps prevent noise. Noise is grainy images caused by digital sensors.
• Choose a fast shutter speed. This reduces motion blur.
• Try using a flash if you’re indoors. Flash adds light to darken shadows.
• Experiment with different settings until you find something you like.