Finding my Grandad (Korean war POW)?

back in 1950 my grandfather was a photographer for the air force. one day he volunteered for a job taking pics of the air strike on a chinese base of ops. Well the air strike never came and the infantry retreated, leaving him and a couple of others alone. The chinese grabbed him and that is all i know. I have a pic, and as soon as i get a scan i'll post it. My dad won't tell me much 'cause he hated his dad. His name was John Henry Newman, and yes, was, i know he died years ago. Can you help me? This is really important to me personally.