Transferring old 8mm home movies to Samsung SMX-F44BN

I am trying to preserve my parents old 8mm projector home movies with a Samsung SMX-F44BN camcorder. What I am doing is playing the movies onto matte photo paper and then recording back with the camcorder. All seemed to be going well at first until I noticed that the camcorder's "focus" keeps dropping out. It will then re-focus but by that time a lot of the footage of the film is messed up. I am not familiar with all of the camcorders various settings. I originally tried doing it with the Smart Auto feature but kept having the focus issues. I then tried putting the camcorder into manual focus mode figuring this should solve the problem in that the focus would stay where I had it set but for some reason even in manual mode the camera still drops its' focus at various times.

Any ideas what may be causing the focus to drop in and out? Why isn't manual focus mode staying at the focus I set it at.