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  1. I recently acquired an AVT-8710 and just went to try it with a copy-protected tape, only to find the contrast blooming astronomically. No such problems with the unprotected retail tapes I've played through it.

    I started with all of its internal proc amp controls reset, and then did brightness -1 and contrast -7 steps in an attempt to recover the levels. As you can see, this failed:

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    Without the TBC in the chain, everything is well within limits of the ATI 600's default settings (but the Macrovision causes the driver to garble the video every few seconds).

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  2. Member DB83's Avatar
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    Of course there are a few variants of mv on VHS. Maybe the AVT can not handle this type.

    I guess this is just a test since surely the dvd of this would give you better quality.
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  3. Yep just a test. I've tried five protected tapes now, including the one that I was planning on capturing for real, and they all do this.
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    The 8710's automatic gain control is a poor performer. Running freaky old EIAJ tapes I got blasted whites with little contrast. (No such problem going directly into the ADVC110 capture card.) I had to insert a proc amp ahead of the 8710 to smooth out sync and video levels. Macrovision messes with levels, so I'm not surprised it would give the 8710 trouble.
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  5. The reason I got it is because people recommend it to remove MV, so you can imagine my displeasure.
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    Last edited by sanlyn; 19th Mar 2014 at 08:50.
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    My 8710 has performed well otherwise, especially considering its low cost. Maybe vaporeon should try exchanging the unit to rule out defective parts. Also, the Canopus (Grass Valley) ADVC110 capture card has a secret switch to disable Macrovision.
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  8. Originally Posted by sanlyn View Post
    The product apparently has QC problems, and it depends on where that copy was purchased. Many fakes are sold on eBay and elsewhere. Mine were from B&H Photo, which gave no argument when I asked to return one that developed bad connectors after a while. The new one worked OK.
    To my knowledge, yes it does have QC problems but it does not matter where it is purchased - 8710, or CTB-100, or other rebrand (not fake copies) have all had defective units for years. It's a gamble anywhere you buy. The model was updated years ago with a different chip, and the mfr seems to think it is of quality since nothing has changed. Whoever owns one that works as intended, consider yourself lucky, from all reports it was a great TBC.

    The last known good model was apparently the green and black AVT-8710, which you could only find 2nd hand now and is rare to come by. I own one of the newer models, and yes it's garbage, it performs poorly as a TBC (freezing/ghosting etc.) and even poorer as a proc amp, given that the proc amp just chooses to do its own thing.

    In the past I would've recommended Datavideo TBC-1000,
    which I've personally been very satisfied with, but it was quite costly new and is now discontinued. In which case, the best option now I think is the DVD recorder passthrough method you've recommended. Pretty easy to acquire, all Panasonic models from ES10 to ES25 have the same line TBC + frame sync ability so it it is a guaranteed and most affordable option.
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  9. Originally Posted by sanlyn View Post
    I usually stick with my Toshiba RS-XS34 or Panny ES15 as pass-thru, which almost always ignores Macrovision on VHS.
    What's your method for determining whether your tapes are protected? I've had the opposite experience with my MV tapes and the DMR-ES15; it inserts new digitally-timed MV pulses in the vertical blanking interval, and also boosts the contrast but not as much as the AVT-8710.

    Originally Posted by SixFiftyThree View Post
    The last known good model was apparently the green and black AVT-8710, which you could only find 2nd hand now and is rare to come by.
    This is what I have. I bought it from a guy who was leaving the country and unloading a ton of A/V and computer gear. At least I didn't spend much.
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    Last edited by sanlyn; 19th Mar 2014 at 08:50.
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  11. well, in my experience, with commercial tapes, there are three popular signs of mv: color displacment or fading in/out, image curling or taring, and agc distruption or color burnout. the first two are easily correctable.

    however, the third one (agc) is not so correctable, if at all. but how badly the results are will depend on what capture equipment or video processor are connected to each other. i use my Galaxy Quest vhs as the guage for this mv since it is very pronounced. i have tried many different equipment scenarios and still haven't been able to fully resolve it for this tape. so, one has to decide if it worth using the ES10/15 and the mv releated agc problems.

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  12. I ran into this problem with my AVT-8710, but it was a very unique case. I have a few Disney cartoon tapes that were dubbed onto Betamax (immune to Macrovision) that were causing the AVT-8710 to completely blow out the contrast. Yeah, somehow the Macrovision protection (whatever Disney was using in 1992) survived the dub. Whats weird is that the VHS originals do not trigger the same problem with the TBC. Your TBC captures show luma being clamped down, was that with the internal proc amp enabled?
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  13. Originally Posted by NJRoadfan View Post
    Your TBC captures show luma being clamped down, was that with the internal proc amp enabled?
    Originally Posted by vaporeon800 View Post
    I started with all of its internal proc amp controls reset, and then did brightness -1 and contrast -7 steps in an attempt to recover the levels.
    By default it was blown out to the top range of the ATI 600's capture ability. Lowering it produced the same level of clamping, just shifting everything downward.
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