HDMI is the standard for output to HD TV's and monitors. I have continuous problems outputting to my HDTV using the mini-port adaptor and those frustrating dongles. Why won't Apple put an HDMI port (or two) on their MacBooks?
My external monitor was working as advertised in clamshell mode. It just suddenly started working only intermittently and not at all in clamshell mode. I'm starting to believe that yet another miniport dongle has gone bad. I'm ready to go back to Windows because my Dell running Windows 7 works flawlessly. I'll buy a new MacBook Pro as soon as Apple puts a true HDMI interface (or two) on the MacBook; until then I'm thinking seriously about a new Windows laptop for watching TV and working on photographs.
MacBook Pro, OS X Mountain Lion (10.8.5), Connecting to a Samsung HDTV