For video no need to worry about lack of autofocus, so older lenses are fine. If you just want to shoot touristy stuff then use a higher aperture and set focus to infinity. If you are playing around with video for production purposes, then you will need to use manual as the autos are too slow anyway. Manual focus is fine though, it's not hard to work out the focus ring sensitivity, and often the older lenses are easier to focus manually than the newer G lenses.