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  1. I'm on the look out for robust VHS player, with s-video out and all the bells and whistles (aren't we all?) and I keep seeing these Lab/Industrial type VCR's on eBay and second-hand sites. they certainly look impressive, but are they any good for video capturing/transfer, or generally not recommended, what makes them industrial or medical grade?
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  2. If they have a TBC in them, then OK. But I don't believe most of them do. Otherwise you're just overpaying for what you need, in my opinion.
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  3. They tend to be extremely overpriced on eBay. Most of the inflated original retail price was due to the target market being dumb enough to willingly pay it back in the day: the current asking prices are typically based on those ridiculous original list prices, and bear no relation to the actual value of the VCR to a home user today. Often these were merely the standard "pro" models given a bland beige cabinet instead of silver-gray, and not much else to distinguish them (no TBC/DNR). They basically break down into two categories: medical/lab/industrial, and duplication. A few of the med/lab models included special old-school computer connections to interface with other devices, a home user would have no need for this. The duplication models were made for 24/7 abuse, with modular parts for quick repair, but have little to offer a home user and most are VERY used.

    None of these specialty VCRs performs anywhere close to a properly-serviced Panasonic AG1980, JVC DigiPure SVHS, or Mitsubishi/JVC DVHS. If you want absolute top-of-the-heap playback, look for the JVC WVHS (analog HDTV) models. These had audio and video optimizations far beyond lab/medical models. Unfortunately, the WVHS models are very rare, fragile to ship, and difficult/pricey to get repaired. A few members here have managed to acquire and restore a WVHS, and have been very pleased with the results. But they're not for everyone, and I don't think a PAL variant was ever sold in Europe (the JVC WVHS sold in North America were modified Japanese home market units).

    The most "rugged" SVHS VCRs I've ever used were the Panasonic AG1970s. Nothing kills them: they were much more rugged than the later, similar-looking AG1980. The 1970 cannot achieve the playback performance of the 1980, however: the TBC/DNR circuits of the 1980 are far more sophisticated. If you can be satisfied with merely "adequate" playback, the AG1970 is much more reliable (in some cases, it can play back better than an AG1980: depends on the tape). Model variations in UK/Europe differ from North America: your PAL equivalent to the AG1980 would be the NV-FS200, which was somewhat better-made than the NTSC version. The most common failure point in the NV-FS200 is the loading mechanics, repair info on this is available on many European AV forums. Approx PAL version of the AG1970 was the NV-FS100 or 150.
    Last edited by orsetto; 3rd Jun 2013 at 15:13.
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  4. Formerly 'vaporeon800' Brad's Avatar
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    Assuming one doesn't care about DNR, is there something inherent to the AG1980 TBC that would make it superior to running the AG1970 through an external unit?
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  5. Originally Posted by vaporeon800 View Post
    Assuming one doesn't care about DNR, is there something inherent to the AG1980 TBC that would make it superior to running the AG1970 through an external unit?
    Running the AG1970 thru an external TBC does not give comparable results to the AG1980 by itself. It isn't just the TBC that differs, the AG1980 has dramatically more effective DNR that in many cases obviates the need for activating its TBC at all. The "line" TBC in both models works on different elements of the signal than an external full-frame TBC, so depending on the tape you might need to use an external TBC with either VCR. You can turn off its internal TBC, but there is no way to completely deactivate the DNR in the AG1980: if you often need to use an external TBC, the AG1970 might be preferable since all of its processing circuits can be switched off.

    The TBC in the AG1970 is a "first generation" built-in circuit: it is comparatively weak and typically does little or nothing to improve playback. It is stellar at correcting a very narrow range of signal faults, particularly overexposed scenes that have been duplicated to 2nd or 3rd generation (it handles this more effectively than the 1980). The "DNR" seems to be completely ineffective with every AG1970 I've used: color and luma noise remain obvious no matter how you set the DNR switch. You do have some leeway with the picture sharpness slider, and setting the picture switch to "edit" yields a noisy but realistic-looking output that digitizes unexpectedly well with some tapes.

    The TBC and DNR in the AG1980 were designed after JVC had introduced their popular DigiPure circuits. Panasonic attempted to outdo JVC when it created the AG1980: in some ways they achieved this goal, in other ways they failed (results are highly variable depending on the tape). The AG1980 TBC is much more powerful than JVC DigiPure or any other amateur/semipro built-in circuit, being somewhat of a cross between an external full-frame TBC and the line-by-line TBC used by the AG1970, JVCs, etc. So the AG1980 can lock down some tapes that play funky on a JVC or AG1970, but the reverse is also true: the AG1980 can outwit itself and overcompensate for some errors.

    Powerful as it is, I find the TBC in the AG1980 to be overkill in most cases, and usually leave it switched off. The very strong DNR circuit is usually sufficient to correct most any visual problem I've seen (tearing, waving, distortions, noise). Compared to JVC and other DNR designs I've tried, the AG1980 DNR usually provides more realistic and natural results.

    The two big caveats are, not everyone has the same visual taste, and the AG1980 can only be properly evaluated against other VCRs if it has recently been serviced/restored by a competent tech who understands the many gremlins inherent in its design. Unlike JVC, which contains most of its TBC/DNR in a few stable ICs, the AG1980 relies on a huge number of discrete capacitors that age out and fail in unpredictable ways. One could argue that no two AG1980s perform exactly alike, which can get very annoying very quickly. This is why there's such heated debate between those who prefer the JVC DigiPure approach, and those who prefer the AG1980: there is vastly more sample variation between second-hand AG1980s than there is between JVCs with DigiPure. The JVC circuit either works perfectly, or it is obviously, grossly defective: there is rarely a grey area of dysfunction. Panasonic AG1980s, by contrast, vary wildly depending on age and condition. Their performance can blow a JVC out of the water, or be absolutely horrible, or be just enough out-of-spec to make "experts" swear the JVC is inherently far better.

    Its all relative, and any given tape can change your cherished preference completely. I have been thru multiple AG1980s, multiple AG1970s, many JVC SVHS DigiPures, and several DVHS with DigiPure. Each one outshines the others with certain tapes, so I ended up keeping one or two of each VCR on hand to deal with the huge variety of tapes I need to digitize. The trouble with all built-in TBC/DNR circuits is the unwanted artifacts they introduce, made worse by a lack of fine tuning controls. I've been surprised how often I get fed up trying to decide between an AG1980 and a JVC, so just default to using the "weak" AG1970 out of frustration. The AG1970 output isn't nearly as "nice," but its such a relief not to see any DNR artifacts that it often seems preferable. As we frequently say here on VideoHelp: YMMV.
    Last edited by orsetto; 3rd Jun 2013 at 18:56.
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  6. Member vhelp's Avatar
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    there is no mention of SP/LP/EP handling. i assume this discussion is based on SP playback with these decks.

    these days, the most common playback projects are based on home footage or commercial tapes, both in SP, unless the rare occasion of marathon recordings done in EP. i still use my JVC HR-S3910U (purchased in sept/2001 new) for this purpose when content is worth this medium, though now rarely used since 1TB HDD's are cheaper to pick up for such marathons. if and when i do record to vhs tapes in EP mode, i use highest quality (tried and tested of course) fuji pro, but now replaced with polaroid pro, since they are the same quality results, and recorded in the s3910u super vhs et recording mode since this gives me the highest (or, maximum) quality on 6/8 hour recording on standard vhs tapes in ep mode. and since it has the super vhs et feature, my Sharp VC-H960 plays them back perfectly, too.
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  7. Formerly 'vaporeon800' Brad's Avatar
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    @orsetto Hmm. A DNR filter that fixes tearing and waving doesn't sound like my idea of what noise-reduction entails (spatial/temporal smoothing).

    @vhelp Why are you recording to VHS in 2013?
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  8. Member Cornucopia's Avatar
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    I think he mentioned it: "marathon" recording (6-8 hour). Me, I would use a PC-based PVR straight to file (with LOTS and LOTS of drive space available), to maintain quality options.

    Scott
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  9. Formerly 'vaporeon800' Brad's Avatar
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    An 8-hour recording at maximum ATSC rate is only 68GB (2.3% of a 3TB drive) and can be compressed downward from there after capture.
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  10. Originally Posted by vaporeon800 View Post
    @orsetto Hmm. A DNR filter that fixes tearing and waving doesn't sound like my idea of what noise-reduction entails (spatial/temporal smoothing).
    As I said, the Panasonic AG1980 is a strange beast, with no real equivalent in any other VCR. Like any one-off device, it is controversial because there's really nothing you can directly compare it with. The DNR circuit performs the usual color noise reduction and luma noise smoothing, comparable to a JVC DigiPure (but with slightly less obvious temporal distortion artifacts). The 1980 DNR also straightens out the "bent doorway syndrome", ragged frame edges and several other distortions that one would think requires activation of the line TBC. But in many cases, activating the 1980 TBC causes undesirable over-correction artifacts with no added benefit. About the only time I need the AG1980 TBC is to perk up murky 2nd-Gen tapes with mostly indistinct dark scenes: it changes these tapes from unwatchable to watchable (the JVC DigiPure just makes them worse). Oddly this is the opposite of the AG1970 optimization (which excels at over-bright correction). But, even this is not a constant: the JVC DigiPure outperforms the AG1980 with roughly 30% of the "dark" tapes I've digitized. No idea why, but the JVC system corrects noise in outdoor/night darkness much better than it does indoor/artificial darkness. The AG1980 is vice-versa.

    It would be interesting to compare the 1980 DNR with the JVC DNR, with line TBC out of the loop, but unfortunately you cannot decouple DNR from line TBC in the JVCs: both are always on or always off (the 1980 DNR is always on but TBC can be turned off). I suspect the JVC DNR might be just as effective as the Panasonic DNR at correcting distortion without the line TBC: whenever I encounter a tape that benefits from the 1980 DNR but not TBC, I try it in a JVC and sure enough, the same TBC-overcorrection mess is the result. So there doesn't seem to be any particular good reason to couple the TBC and DNR aside from "one big green button for non-techies." European variations of the AG1980 allow complete independent switching of the TBC and DNR, which is ideal: why this option was not implemented in the NTSC vcrs is a mystery.
    Last edited by orsetto; 4th Jun 2013 at 10:07.
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  11. Formerly 'vaporeon800' Brad's Avatar
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    Originally Posted by orsetto View Post
    (the 1980 DNR is always on but TBC can be turned off)
    European variations of the AG1980 allow complete independent switching of the TBC and DNR, which is ideal: why this option was not implemented in the NTSC vcrs is a mystery.
    Is that how you can attribute the signal corrections to the "DNR" circuitry rather than other non-defeatable processing done by the deck?
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  12. Originally Posted by vaporeon800 View Post
    Is that how you can attribute the signal corrections to the "DNR" circuitry rather than other non-defeatable processing done by the deck?
    Since the existence of "other processing circuits" is not described or documented by Panasonic, one can only go by observation with the TBC switched in or out. Geometric distortions are corrected perfectly with the TBC off, turning it on frequently overcorrects and creates an unwatchable mess. Playing the same tape in a JVC, which has the DNR and TBC always coupled, results in the exact same mess. So either the DNR alone would solve most distortion problems with both brands (assuming the JVC DNR could be invoked separately), or both brands employ additional "uncredited" circuits that correct these distortions. The AG1970 can be used as a neutral comparison: it does have independent DNR and TBC, neither of which seems to ever have an adverse overcorrection effect combined with the other. Of course, the DNR and TBC are much weaker in the AG1970, its DNR does nothing to correct distortion, and its TBC only rarely succeeds at this.

    To be clear, I am not fond of the Panasonic AG1980 as an overall VCR. It is one big giant honking PITA, a high-maintenance diva so electronically undependable that it wouldn't be tolerated by anyone if it weren't for its defeatable TBC. Unfortunately, if you want the benefits of modern VHS DNR with the ability to back off on the TBC when the TBC causes trouble, there are no other options. My Mitsubishi HS-HD2000U DVHS vcr (which uses a knockoff of JVC DigiPure) is tremendously more reliable, and while I've had a lot of mechanical issues with my JVCs, their electronics and output quality never varies. If those VCRs had independent TBC control, I would have ditched my Panasonic AG1980s years ago. All things being equal, if all these vcrs had switchable TBC, the only remaining advantage of the AG1980 would be its "full frame" TBC vs the "line TBC" used in other VCRs. That advantage looks good on paper but is not that big a deal in practice: it is optimized for original camera-generated video shot by event videographers. It isn't all that helpful with TV recordings or concert bootlegs.
    Last edited by orsetto; 4th Jun 2013 at 17:01.
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