My rear camera (looking away) is not focusing.

My rear camera (The one looking away from you) is not focusing at all. Everything close-up is fine but I cannot focus on anything far away. I have tried to restart it (holding down the home and power/lock button) and tried tapping it against my palm in case the lens is stuck. It hasn't worked. Do I need to take it to a Apple store?

A hasty reply would be great!!

Thanks for the help!