S-VHS
Official logo of the Super-VHS or S-VHS video cassette format
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| Media type | Magnetic videotape |
|---|---|
| Encoding | PAL, NTSC, ADAT |
| Capacity | 9 hours in super long play (SLP) mode on E-180 |
| Standard | Video cassette |
| Usage | Home video, home movie, educational, video production |
| Extended from | VHS |
S-VHS (スーパー・ヴィエイチエス?), the common initialism for Super VHS, is an improved version of the VHS standard for consumer-level video recording. Victor Company of Japan introduced S-VHS in Japan in April 1987 with their JVC-branded HR-S7000 VCR, and in certain overseas markets soon afterward.
Like VHS, the S-VHS format uses a color under modulation scheme. S-VHS improves luminance (luma) resolution by increasing luminance bandwidth. Increased bandwidth is possible because of increased luminance carrier from 3.4 megahertz (MHz) to 5.4 MHz. Increased luminance bandwidth produces a 60% improvement in (luminance) picture detail, or a horizontal resolution of 420 vertical lines per picture height – versus VHS's 240 lines. The often quoted horizontal resolution of "over 400" means S-VHS captures greater picture detail than even NTSC analog cable and broadcast TV, which is limited to about 330 television lines (TVL). In practice, when time shifting TV programs on S-VHS equipment, the improvement over VHS is quite noticeable. Yet, the trained eye can easily spot the difference between live television and a S-VHS recording of it. This is because S-VHS does not improve other key aspects of the video signal, particularly the chromanance (chroma) signal. In VHS, the chroma carrier is both severely bandlimited and rather noisy, a limitation that S-VHS does not address. Poor color resolution was a deficiency shared by S-VHS's contemporaries, such as Hi8 and ED-Beta – all of which were limited to 0.4 megahertz or 30 TVL resolution.
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