JVC Digital TBC and Panasonic ES10 filter question

[robjv1]

Now I know that the Panasonic ES10 is known to help with the "top image" tearing problem that occurs on some tapes -- I also have a JVC HR-S7600U VCR (that I love) that occasionally with the digital TBC engaged causes causes the top of the image to skew. Now I assume the ES10 filters can fix a tape with the top-image scew when it's native to the tape, but my question is can it also correct this problem when the skewing is caused by the JVC's digital TBC?

Thanks again!

[Barnabas]

I doubt it. I own a JVC HR-S9911-U as well as a stand-alone TBC. While using both the internal TBC and the external one on most tapes works ok, for tapes that get the top bending, only turning off the JVC's TBC stops the problem.

[robjv1]

Yup that's what I normally do (I have a Data Video TBC-1000 too) but the JVC Digital TBC does so much for the picture quality on some tapes that it's a shame to have to turn it off, so I was wondering if anyone has tested or tried this and what kind of results they had.

[lordsmurf]

Yep, what Barnabas said! Turn off the JVC TBC and let the Panasonic filters do their job instead. The JVC can still serve some functions in this situation, with a stable playback, stabilizer (if needed), picture filters and audio mode selection.

[robjv1]

Since the top-screen tearing is only occuring on these tapes when my JVC TBC is engaged and isn't present at all when it's not, what other benefits to the picture will the Panasonic provide? I was only aware of the filter that seems to fix the top screen tearing.

My top screen tearing issue is not present in this case with the TBC turned off, it is created when it's engaged. So what benefit will the Panasonic have since I have to turn off the JVC TBC (which gets rid of the problem) anyways?

[lordsmurf]

That's the big one. Panasonic has some more filters, but they tend to add more posterization and some temporal ghosting. It's one of those trade-offs you have to deal with to stabilize the video.

Your source video sounds like it's not very good. You're going to have to pick the lesser of evils.

Panasonic has some filters that sometimes remove a portion of chroma noise and grain, similar to the JVC S-VHS, but again, it comes with other flaws.

You'll have to make up your mind what looks the best from the combinations of options available.

Another VCR might even help, be it a normal VHS machine or a Panasonic S-VHS VCR, for this one tape.

[davideck]

My top screen tearing issue is not present in this case with the TBC turned off, it is created when it's engaged. So what benefit will the Panasonic have since I have to turn off the JVC TBC (which gets rid of the problem) anyways?

Frame Synchronization.

Like other DVD Recorders, the ES10 contains a TBC/Frame Synchronizer that provides the same Frame Synchronization capability as an external TBC. The video input is digitized, stored in memory, and then synchronized and combined with an internally generated composite sync source which is stable and continuous. This eliminates audio/video sync issues with many capture devices as well as the DVD Recorder itself.

The JVC VCRs with TBC/DNR do not provide Frame Synchronization.

[robjv1]

Well I have an external TBC, so I suppose I don't need the ES10 for frame sync and I haven't found any recordings thus far that exibit the top-screen tearing problem that aren't directly caused by turning the JVC Line TBC on. If the TBC is off the tearing is not present (though the picture quality certainly drops off) The tearing does tend to manifest itself in a couple of my really old tapes that are pretty bad source tapes, but I've also seen it on commercial tapes that have been played very little that exhibit the same error on occaion. Maybe just a little quirk of the JVC TBC, trying to over-correct perhaps? There is always trying out another VCR I suppose. I have an BVP-4 on the way that will hopefully allow me to address the color issues this very old VHS tape.

It's a fun (but expensive) challenge that's for sure! I started out coming in here maybe a year ago now with nothing but a Go-Video dual deck VCR and have since collected a great video monitor, the panasonic DMR-ES10, a Vidicraft VDM-100 combo proc amp / sound unit, a DataVideo TBC-1000, a JVC 7600U, and now the BVP on the way. I must have spent about $1000 which is probably a pretty decent deal for most of that stuff.

[lordsmurf]

the ES10 contains a TBC/Frame Synchronizer that provides the same Frame Synchronization capability as an external TBC. .

This is not true.
The external TBCs do not provide the same function as the ES10 does.

The standalone TBCs cannot correct the tearing like the ES10 does.

[davideck]

the ES10 contains a TBC/Frame Synchronizer that provides the same Frame Synchronization capability as an external TBC.

This is not true.
The external TBCs do not provide the same function as the ES10 does.

The standalone TBCs cannot correct the tearing like the ES10 does.

I am not disputing your claims about the ES10. You are comparing Timebase Correction capability while I am comparing Frame Synchronization capability.

Frame Synchronization and Timebase Correction are independent functions. Frame Synchronization is performed on the read side of memory to guarantee continuous sync at the video output. Timebase Correction is performed on the write side of memory by deriving a suitable sampling clock with which to digitize the video input. The characteristics of the sampling clock determine the Timebase Correction capability.

All Frame Synchronizers must digitize their video input. They all must therefore derive a sampling clock. As such, they all have some inherent TBC performance. Under various source conditions, some can make things better while others might make things worse.

It is the Timebase Correction capability that varies among the different built in or external TBC/Frame Synchronizers. For tearing errors, the ES10 may in fact do a better job of Timebase Correction than your external TBC. For other types of timebase errors, the external TBC may perform better.

But they both provide Frame Synchronization.

[lordsmurf]

Different ones work differently, that's all I'm getting at. I don't want somebody to think just any external TBC is going to fix this problem.

[robjv1]

You know what ended up helping? Unplugging my JVC 7600u for a bit, powering it back up and trying again. It gets screwy sometimes and then the TBC will seem to not work correctly and create more errors then it fixes. The SVHS-ET light comes on often when regular VHS tapes have problems tracking or playing. After that they don't seem to play quite right until I unplug it. Strange little quirks!

[lordsmurf]

Have you considered power issues? The unit may be getting spikes, dips and surges! YIKES! Be sure it's on a sruge protector at least, preferably a voltage-regulated UPS.

[robjv1]

It's on a surge protector as are all of my video devices, but they are getting pretty old. I should probably get some replacements. Any suggestions for them or for a voltage regulated UPS?