HELP Can't get rid of lines introduced by Time Based Corr.

[720phd]

Hello,

I am attempting to capture VHS to DVD and after much reading, I am getting pretty close to my desired result. Unfortunately, I am on my second TBC, an AVToolbox AVT-8710 and a DataVideo TBC-1000. Both introduce solid, steady vertical lines into the image. That's a problem. Plus, none of the clean filters seem to correct them. I have attached an image that shows the lines as alternating shades of blue.


(easier to see if you save image and zoom in)

I am using VirtualDub to clean. I have tried most built in filters, plus VHS, TV, 2d Clean, etc...

I have moved wires away from interference, connected equipment to power on separate circuits. I have eliminated my capture card and VCR from blame by witnessing the lines without either in the series of connections (i.e DSS to TBC to TV).

Anybody have any ideas as to why this is happening, or what it is, or how it can be corrected?

Thanks,

Clark

[rgscout]

I red on this forum that´s possible to correct the video signal using Digital Camcorders( passthrough trick ). I think that´s is cheaper than TBC option.
I´m looking for that post. But I´m sure I saw.

What you trying to do is useless because the problem is in the source and the filters on virtualdub can´t correct this kind of problem.

Thanks

[txpharoah]

I red on this forum that´s possible to correct the video signal using Digital Camcorders( passthrough trick ). I think that´s is cheaper than TBC option. I´m looking for that post. But I´m sure I saw.

No.

What you trying to do is useless because the problem is in the source and the filters on virtualdub can´t correct this kind of problem. Thanks

Yes.

A TBC-1000? Well, it's not likely to be the TBC. Though have it checked out on another tv and vcr with another tape to be sure.

The problem may be bad wires, overloaded electric outlets (be sure to run a high-quality extension cord to another entire circuit, as several plugs in the room may be the same circuit) which usually causes chroma noise, bad source tape to start with.

What does the video look like without the TBC?

Try out what I suggested and post results. I've dealt with odd errors like this numerous times.

And the bluescreen is no kind of test. The VCR may just emit a crappy-looking bluescreen. One of my best machines does that.

[720phd]

The lines are made visible by the TBC but I think it is resolving something in the signal that is not visible without the TBC. i.e. the blue screen is perfectly smooth without the TBC. But then I have all the stability problems that are corrected by the TBC. I used the blue screen because it is easy to see the lines. I first noticed them when viewing captured footage. I can detect the lines to various degree when running several video sources through the TBC: multiple VCRs, DSS receiver, DVD player. S-Video, composite video. However, when you run color bars from a signal generator, there are no lines.

I've tried powering from separate circuits, checked voltages and power supplies.

Any ideas are appreciated. In a few weeks, I hope to take the equipment to a local video production facility and see if they can diagnose. Cause I gotta know why

[davideck]

I have a TBC-1000 and have noticed the same thing, but only on a low luminance blue screen. I haven't noticed it in any of my captures of VHS / SVHS. I will take a closer look. Do the lines make it onto the DVD, or just your PC display?

[txpharoah]

Could it be the capture card?
Or some other kind of interference (as in your video equipment being too close to the computer)?

[vhelp]

hi 720phd,

Many people are only now beginning to (admitingly) experience this noise
issue.

I have ben their and pretty much done it all - the tests and stuff to find the
cause of Line Noise you are describing. They do come in various
forms.

I've pretty mouch narrowed it down to two main ingrediants.. and no matter
what card you use, you'll no doublt, end up seeing some level of noise, though
some cards may work better w/ lesser noise.

In my earlier testing stage of my new Osprey-210 card, I made claim that
it didn't produce any noise. It does, but is minimal when used with my
Satellite, though still noticable (and annoying) However, when using VCR
as your source (VHS) the noise is much greater. And, I'm not taslking
about the VHS tape's noise.

..I've pretty mouch narrowed it down to two main ingrediants.. I was saying..

It's down to the:
* Motherboard/Chipset/CPU, and
* the Capture card.

Note..
If you want to make a demo of noise in your source to show others here, you
can just setup your card's capture app, and instead of capturing your source
ie, Satellite, turn off your Satellite and just capture the blue screen. This
is more than enough for that test. Weather there is source signal or not,
it does not have (or influence) noise lesser or greater. It will be the level
of noise in either case.

The Noise..
Is deffinately comming from the Motherboard make. The motherboard I was using
that showed no noise, back a year ago, was my old:

* K7T Pro2-A (MS-6330) - Athlon 900mhz w/PC133 128mb ram (last upgrdd 03-10-01)
* ATX VA Mainboard w/VIA chipset
* ATI-TV Wonder capture card

And, based on memory, my captures were always clean. At least my old MPEG-2
clips on CDR are all clean.

This board was replaced because (in short) I fried the CPU chip (faulty fan)
by my latest motherboard: ESC K7S5A w/ XP 1800+
..which happens to be Noisy in all my capture cards

The catch, in my setup is the Motherboard I was using at THAT time of
capturing.
But, I need to verify all this.. which may take time.

-vhelp

[720phd]

Now that I have an eye for them, I can see the lines from the capture screen all the way through the process to DVD Video. They seem to be more noticeable when you have a static background (like a talk show), and especially reveal themselves when the static backgound makes the occasional pan. I first noticed them during a David Letterman monologue.

The problem is not introduced by my PC or capture card, as I can see them when connecting VCR to TBC to TV. The TBC is definately the device that makes the lines visible.

[txpharoah]

I'd return it for being defactive and get another one. That's not common. Noise as you state is normally from power issues or interference. The card and other things too, but the important part is testing out different scenarios.

[sanlyn]

I see those lines when my VCR or signal source is not emitting a signal to the TBC. In my recording from a VCR, I sometimes hit the "Record" or "Capture" button, and the screen is blue because I haven't started the VCR PLAY yet. As soon as I hit PLAY, I no longer see the lines you describe, even though the output is a blue screen for the first few frames of recording.

My TBC is the AVT-8710, capture card is ATi AIW 7500 and an AIW 8600XT.

[jolphil]

Hi,
Near as these old eyes can see,you have about 17 bars on each horizontal line..Each line is approximately 63.5 microseconds (ignoring blanking period) or 15,750 HZ..17 times that
would be an interferring signal of about 267Khz..Those types of signals most probabily would come from your TBC's internal circuitry..As I think you mentioned,the lines occur only when the TBC is involved..Possibly poor shielding of the circuit board..Thats just a guess from viewing your screen shot..
Maybe someone more knowledgeable might comment..
Anyway thats just my guess..
jolphil