screen goes dark when enlarging text or imessage

[bkushner]

Iphone 5S...when I get a text or Imessage with an image and I pinch to enlarge the image screen turns black?

 

[KevinJS]

Try restarting the phone. No idea why it should be doing that but rebooting the phone usually sorts things out when apps misbehave.

Hold home and lock buttons until the Apple logo appears, then release them and allow the phone to restart.