Built in flash techniques: 05. Slow-sync
Although a burst of light from your camera’s pop-up flash will illuminate your near-by main subject, it’s power falls off quickly and the background will not receive a significant amount of light.
This means that you can wind up with a brightly lit subject in front of a dark background.
However, if you extend the exposure time the brightness of the background will increase without over-brightening the subject – although you may find that you need to adjust the flash exposure compensation a little.
This technique of using a slower shutter speed with flash is known as slow-sync. It’s useful for injecting life into the subject and separating it from the background.
Although the subject will be frozen by the flash, the long exposure for the background may mean that the camera needs to be on a tripod to prevent it from being blurred.
However, if you pan with the subject it can be rendered sharp by the flash while the background is blurred.
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