CompuServe Messages

I've rendered a 3DS file to a series of numbered .tga files, which I had hoped to record to videotape using the Disk-to-Tape command with a Diaquest DQ-422 animation controller and Panasonic 7750 VTR. My concern is that it seems as if it takes longer to output to tape this way than if I had rendered straight to videotape; the rendering of the individual .tga images took roughly 30 seconds, while the output to tape takes a great deal longer. Is this to be expected?