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| Archivability | Good quality tape can be relied upon to withstand a wide range of temperature and humidity. If stored properly, the expected lifetime of a video tape should be anywhere from 10 years to beyond 30 years. Tapes should resist shedding and layer-to-layer adhesion; remain flexible; and retain the recorded signals with little loss. Poor performance tape may start shedding over time especially if exposed to extremes of temperature. Also they may develop sticky substances as a result of high humidity exposure and the breakdown of the vinyl binders used to hold the magnetic particles onto the base film. |
| Audio Frequency Response | This is the measure of relative loudness of high frequencies compared to the playback level of the lower frequencies. It is measured at 7 Khz. |
| Audio Sensitivity | The playback output level of the audio signal at lower frequencies (measured at 1 Khz). This represents how loud the audio signal will be on playback from conventional linear audio (not hi-fi VCRs). |
| Color Noise | Better known as chrominance signal-to-noise ratio. A measure of how accurately the color signals are reproduced. Poor chroma signal-to-noise ratios are evidenced in color fringing on edges of objects and what appears to be thousands of moving dots in large areas of highly saturated colors (especially red). |
| Color Output | The playback output level of the color (chrominance) signal after it is separated from the luminance signal. As with RF output, a low performing tape can lose color resolution due to increased percentage of noise. |
| Dropouts | Those black or white streaks, spots, and comets zipping across the screen. We count as dropouts any loss of playback signal that is 20 decibels or more below the nominal playback level (16 decibels for extra high-grade and 8 mm tapes) and lasting for 15 microseconds or longer (about one quarter of one horizontal scan line on the TV screen. |
| Electrical Performance | The electrical performance of the tape samples is measured and compared to the VHS-standard reference tape (the JVC VRT-2). The published numbers represent how much better (+) or worse (-) than the industry standard tape each tape sample performed (the VRT-2 scores 0.0 for every parameter). |
| Extra High Grade | A truly high grade tape will demonstrate its differences mostly in the quality of the image recorded. Extra high grade tape coatings are generally superior in noise immunity and lower in dropouts. This means that you get a better recording, and you'll get a better second and third generation copy. Several manufacturers have indicated on their packaging that they have done things to also provide greater longevity, but this is a claim that would be difficult to prove or disprove. For especially valuable recordings, use a high grade tape; but remember that there is no standardization and no requirements that prevent anyone from naming a product "extra high grade." Buy a tape with a brand that you trust. |
| RF Output | The playback output level of the recorded FM signal. Lower RF output levels can result in increased noise levels in the playback signal. |
| Video Noise | More commonly called "luminance signal-to-noise ratio." This is a measure of how pure the video signal is (the monochrome or black-and-white portion of the picture). Tapes with good luminance signal-to-noise ratios have sharper, clearer images. This property has even greater importance on multiple generation copies. |