I needed to capture gameplay to get some illustrations for papers and my thesis. Also, videos are good source to double-check details later. I did have software for this in my use while I worked at Tampere. Now I needed to figure out solution for OSX. The choice was ELGATO EYETV HYBRID which has functionality needed. Software works fine for capturing; unfortunately my Powerbook G4 is not updating screen without lack when recording. The solution for this is to split the signal for television and laptop, and use television to play.
(P.S., publishing screen captures and making recordings for scientific use are legal, with few limitations, in Finland, see tekijänoikeuslaki, 2.14.)