I would greatly appreciate if anyone could give me tips on how to demount a photo? It was framed and the picture has been glued to cardboard. Any tips would be greatly appreciated.

If it was drymounted (not unusual) a hairdryer might work.

The picture in question is an Ansel Adams photo. The Death Valley Sunrise one. Would it be safe to use a hairdryer, or am I better off taking it someplace?

If it's an original, I'd DEFINITELY take it someplace. Your local history museum should be able to recommend a conservator. If it's a poster, just buy a new one, it won't be the same after unglueing.

Yeah its a real photo and definitely not a poster. I bought it for $10 dollars at a garage sale. I just was not sure about the value of the picture. Its a smaller photo and the mount is really way to big. It looks like somebody who owned it before me started to take the cardboard backing off but must have thought better of it. The picture looks to be in perfect shape though.