iSight not Working with Messages/Facetime

I have a MacBook Pro 13 inch mid 2009 that I connect to a 22" cinema display (very old but still works beautifully) and I have an older cylindrical iSight camera mounted to the top of the cinema display (laptop is closed and cinema display is only monitor in use). It has always worked fine. I connect the iSight to a firewire hard drive and the hard drive to the fire wire port on the MacBook Pro. Today I am still able to get the isight to work in iMovie. So the camera works, the wiring works.

However, recently I haven't been able to get facetime or skype to recognize the iSight camera. Why is that? How can I facetime with my camera? I don't want to open up my laptop everytime my wife calls.

I have MacOS 10.10.2.