Yamaha AVC-50 AVC-50 OWNERS MANUAL - Page 16

tsVC-50 USIND THE VIDEO ENHANCER The Video Enhancer circuit is designed to improve the image quality of any video signal, when viewing, recording, or dubbing between sources. The Video Enhancer boosts high frequency information, enabing it to increase both detail and sharpness. Since image enhancement is proportional to source material quality, the better the original, the greater the improvement. Poor source material can only be enhanced with minimal results. This is due in part to the fact that video noise (snow) is in the same frequency range as detail and sharpness, so when you enhance detail and sharpness, you also enhance snow. (Sncw is comparable to hiss in a high fidelity audio system.) Detail and sharpness are inter-related, but distinct, aspects of picture quality. Lack of detail shows up as smeared pictures or pictures lacking subtle texture, while lack of sharpness shows up as indistinct lines and edges. When recording from a camera or television tuner, use the Video Enhancer to exaggerate detail. This will precompensate for the loss of quality due to the video cassette recorder and produce a tape with all of the original detail. When mak ng tape duplicates, use the Video Enhancer to retain most .of the original's detail and sharpness. If the original is very snow-free, the copy can look better. When viewing a video tape recording, use the Video Enhancer to compensate for lose of quality due to the video cassette recorder. Controls The ON/OFF switch is used to engage the Video Enhancer circuit:, Press the switch once to turn the Enhancer on (the switch stays in). Press it again to turn the Enhancer off. The PB/REC (Playback/Recording) switch is used to select the signal to be enhanced. When the switch is out, video enhancing s performed on the video source signal being monitored. When the switch is depressed, video enhancing is performeJ on the video signal going to a video recorder. If this switch is pressed during video recording, the picture will gc blank for a few moments. 16 The SHARPNESS rotary control is used to increase the sharpness of the picture and to also bring up some detail. Turn the control completely counterclockwise to eliminate its effect Turn it clockwise to adjust for maximum sharpness without creating false outlines. The DETAIL rotary control is used to compensate for detail loss. Use it to exaggerate detail before recording and/or to restore detail during playback. Turn the control completely counterclockwise to eliminate its effect, Turn it clockwise to adjust for natural detail and acceptable snow. The VIDEO LEVEL rotary control is used to control the overall level of the video signal from a source. It is similar to the brightness control on your television. This control has no effect on the video signal when it is in the center position. Turn it clockwise to increase the video signal level and counterclockwise to decrease it Effects To obtain the best results from the Video Enhancer, you should first check the effect of each control separately, as well as their interaction. 1. Make sure all controls are set to their defeat positions, and the PB/REC switch is out. 2. Select a broadcast program to obtain a high-quality source image. Remember, the better the source the more obvious the enhancement. 3. Tum the VIDEO LEVEL control and note its effect The image becomes brighter as you turn the control clockwise and darker as you turn it counterclockwise. Set it to a desirable level and note its position. 4. To judge the improvement, press the ON/OFF switch to compare the before and after enhancement images. 5. Return the VIDEO LEVEL control to the center position. 6 Turn the SHARPNESS control and note its effect. The edges and contours of objects and people should increase in sharpness as you turn the control clockwise. If you continue to turn the control clockwise, sharpness will be exaggerated and false outlines will be created. Turn it back to a desirable level, where the outlines are acceptable and the images natural. Note the controls position. 7. To judge the improvement, press the ON/OFF switch to compare the before and after enhancement images. 8. Return the SHARPNESS control to the extreme counterclockwise position. 9. Turn the DETAIL control and note its effect The textures of clothes, distant background, and people should increase in detail as you turn the control clockwise. If you continue to turn the control clockwise, detail will become coarse and the picture will have increased snow. Turn it back to a desirable level, where snow is acceptable and detail natural. Note the controls position. 10. To judge the improvement, press the ON/OFF switch to compare the before and after enhancement images. 11. Return the DETAIL control to the extreme counterclockwise position. Viewing Before using the Video Enhancer for viewing, make sure that the controls are in their defeat positions, the ON/OFF switch is in, and the PB/REC switch is out The correct sequence of adjustment is Video Level, Sharpness, and then Detail. Judge the enhancement results from your usual viewing distance When you view a television broadcast, the amount of improvement depends on the quality of the broadcast. Some broadcasts are already enhanced and will not require further enhancing, while other broadcasts may require detail and/or sharpness enhancement.