I am forwarding the following on behalf of Joey S. Schwartz--his computer and that of screen-l have had a tiff and aren't presently speaking to each other. It's a reply to a message I sent him about his screen-l posting on resolution. --Keith Nightenhelser [log in to unmask] ------------------------------------------------------------------------------ From: IN%"[log in to unmask]" 5-AUG-1993 03:20:39.03 Subj: Fwd: Re: resolution Organization: Inter/Access, Arts Telecommunications & Media Centre, Toronto, ON, Canada Content-transfer-encoding: 7BIT Here are more accurate numbers, but the way that video is compared to film is not by screen size (because film is usually projected at non-standardized lengths for one thing) but by resolving power per one square inch, which is the same for a T.V. image that is one inch or 100 inches. Another consideration in video is bandwith, for every 1 megahertz of bandwidth equals 80 scan lines (not to be confused with lines of resolution). So a tape format like VHS, which has a bandwidth of 3.5mhz, has only approximately 240 scanning lines, which decreases the overall resolution of the NTSC signal. SO here are the "official" numbers from Thomas A. Ohanian's book DIGITAL NONLINEAR EDITING: New Approaches to Editing Film and Video: FORMAT LINES OF RESOLUTION VHS 200 SVHS 272 STANDARD 3/4" 240 Laserdisc 336 Hi8 320 (luminance portion of the signal) Betacam 288 Betacam SP 336 2" Quad 336 1" Type C 336 D1 336 D2 336 D3 255 35mm Film 6x resolution of average "broadcast picture" [2016 for regular film, 5247 has over 4000 lines of resolution according to Kodak] (from Ohanian, 212)