Down conversion from HD to SD (Standard Definition) means that you will be reducing the resolution of your video or film from 1080 or 720 horizontal lines of resolution to 480 lines of horizontal lines of resolution or SD (PAL 576). Your video will still be high quality SD, but you shouldn't expect it to be the resolution of your HD master. When viewing your SD DVD on an HD set, you will likely notice a reduction in resolution, but no more than any other SD DVD.