Using aperture and shutter speed in Program mode
The two key components in making an exposure are aperture and shutter speed. As the aperture gets larger, more light reaches the camera’s imaging sensor.
As a result, faster shutter speeds are needed to reduce the amount of time the sensor is exposed to the light – otherwise the picture will be too bright.
Similarly, as the aperture gets smaller, slower shutter speeds are required to increase the amount of time the sensor is exposed to the light – otherwise the picture will be too dark. It’s this balancing act that Program Shift is based on.
As you turn the camera’s control dial, the combination of aperture and shutter speed changes, but the overall exposure remains consistent.
See our example above: each of the combinations shown here would give the equivalent exposure, but the effect on the image at each end of the scale would be very different.
Bear in mind that the actual combination shown on your camera will vary according to the amount of light available, the metering mode and the ISO sensitivity set on the camera.
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