iOS 8 allows you to manually adjust the exposure when taking a picture. This allows you to brighten or darken your picture. Once you have tapped the screen to focus, a yellow box appears around the focal point. A small sun icon appears on the right side of the box. Tap and drag the sun up to increase exposure (brighten) or down to decrease (darken).
How do I change the iPad camera's exposure in iOS 8?
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