1. Tap Store tile to see if there are any updates available for your camera app.
  2. Restore the default camera settings, go to Settings and then swipe left to applicationsphotos+camera (pictures+camera). Scroll down to the bottom and tap reset camera.
  3. Switch to the front camera (optional) to see if it makes a difference.
  4. If the problem persists, reset your phone. Press and hold the Power and Volume down keys simultaneously until you feel the phone vibrate. After this operation, you may need to set the date and time on the phone.