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VHS and SVHS tapes use the same decks at Access SF. Although SVHS is a higher quality than VHS when everything is working well, they both suffer from the same problems.
VHS and SVHS tapes are analog recordings and the problems mentioned in this article can be eliminated only by using digital recordings and tapes (i.e., DVCAM, MiniDV).
When copying from, to, or between analog devices you will get a generational loss of quality. We've all seen that in photocopies of photocopies, and we've all seen that on Access SF, with shows that appear blurry. The only way to prevent generational loss is to use digital media (i.e., DVCAM, MiniDV) with digital connections (i..e., Firewire).
VHS and SVHS tapes have no timecode. Tape locations are based on displacement from the beginning of the tape, or more practically, displacement from where the tape was when it was inserted into the deck, or when the tape counter was last reset. Another factor is that measuring this displacement differs between decks.
When timing tapes for playback, and best practices are followed, the tape is inserted into a deck, the tape is rewound, and the counter is reset. Then the tape is played until the beginning of the show. The tape time is noted as the start time. If the person doing the timing does a scan fast forward (Play -> Fast Forward) to find the beginning of the show, the deck may measure tape displacement differently and the start time may be a second of two off.
After the start time is noted, the tape is fast forwarded approximately 28 or 58 minutes to where the show is expected to end, then we search for the actual end of the show and note the end-time. This fast forwarding will measure tape displacement differently than if the tape was actually played. The scanning to find the end of the show will measure tape displacement differently than playing the tape. These difference could add up make the show appear to be miss-timed be a few seconds. There is not enough time in the day for staff to time tapes by playing the entire show.
The final variance occurs because the decks used for the actual playback, measures tape displacement differently than the decks used to time the tapes.
If the tape timing variances of using VHS/SVHS tapes in unacceptable, then use digital tapes (i.e., DVCAM, MiniDV).
With analog recordings, there is no timecode available to synchronize the frames. Tracking alignment differs across tape decks. The playback decks at Access SF are aligned regularly. Your consumer deck at home may have a tracking alignment procedure, but I've found that most people have no idea how to align their decks. When you record a tape on a misaligned deck, it may play perfectly on that same deck, but may appear distorted on another. Much of the video distortion you see on Access SF is related to miss-tracking.
The professional playback decks used for playback receive regular maintenance, including tracking alignment. Staff occasionally get phone calls from producers complaining about how their show is playing. The problem is often a tracking problem. The producer may request that we adjust out decks to optimize playback of their show. Zane Blaney as forbidden us from doing that, and for good reason. Our decks are aligned, and we should not be suboptimizing our decks to compensate for one show, because that has a detrimental affect on all other shows that will later play on that deck. Even though, if staff is available through that show, some staff have risked tweaking alignment for one show if they know they can reset the alignment before the next show plays. I agree with Zane that we should not do this, but I've done it on occasion when I knew I would be in playback as the show ended allowing me to reset the deck. In those situations I left a note with he tape for the producer to align their decks. On occasion producers have asked me to tweak a deck's alignment and I was unable to comply since I knew I wouldn't be there when the show ended. I would not risk adversely affecting all following shows on that deck for the sake of a single show recorded on a miss-aligned deck. I believe Zane is absolutely correct that staff should not be tweaking deck tracking alignment for any show. It is the producer's responsibility to submit a quality tape for playback
To avoid tracking problems, use digital tapes (i.e., DVCAM, MiniDV).
VHS has multiple audio formats. The two primary formats are Normal Stereo and Hi-Fi Stereo. Normal Stereo embeds the audio within the video track. This format has been obsolete for over 20 years, when Hi-Fi Stereo was introduced and recorded a higher quality audio in distinct stereo tracks separated from the video track. Most decks can be configured to specify how audio is recorded. Most record both Normal Stereo and Hi-Fi Stereo, and playback Hi-Fi Stereo. How is your VHS deck configured?
Consumer decks use the same stereo RCA connections for both Normal and Hi-Fi audio output. Access SF's professional VHS/SVHS playback decks have distinct audio outputs for Normal and Hi-Fi stereo. Zane has opted to support the lowest common denominator, so only the Normal Stereo audio jacks are connected for playback. It is best to record tapes with Hi-Fi Stereo, but you must ensure that the Normal Stereo tracks are also being recorded.
You may see some shows on Access SF where you can't hear the audio. Often it simply that the producer doesn't understand audio recording levels, but sometimes it's because the VHS tape neglected to record the Normal Stereo tracks. In those situations, the only way to hear the sound track is to rewire the playback deck, and Zane had forbidden that for good reason. We cannot risk adversely affecting other programming for the sake of a show that neglected to properly include a Normal Stereo audio track.
The only tape speed that Access SF supports is Standard Play (SP) speed. Occasionally we get tapes recorded in other speeds (i.e., SLP, EP). Those tapes will not play correctly.
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