Datavideo TBC1000 introduces cross-hatching to picture

[andrewjameshoward]

I just bought a TBC1000, allegedly new but old stock. It seems to introduce a diamond latticework pattern to lighter areas of picture - look at the guitar soundboard in the second picture. A bit fuzzy in a still, but in motion, very visible as a constant pattern in the lighter areas - I would guess it pervades the whole picture like an overlay. Can anyone tell me what it is?

[orsetto]

It could be several things. TBCs are not a cure all, they fix some serious problems but they also introduce their own artifacts, mainly a general softening of the image and occasional herringbone or diamond crosstalk patterns that can be difficult to isolate and remove. Among possible TBC issues:

Is the problem limited to just one or a few tapes, or all of your tapes? Some tapes are just resistant to "improvements", they cause conflicts and are best dubbed straight across warts and all with no TBC or other ancillary hardware in the middle.

What type of VCR are you using as the source? Does it have its own internal noise reduction or TBC feature? If so, try turning it off: internal and external DNR and TBCs operate on similar-but-conflicting principles that often lead to undesirable interactions. Run some sample tests and decide which TBC gives the best overall result: the one in the VCR, or the TBC1000. Don't use both at the same time. Also, try switching to a completely different VCR (different brand altogether).

Check your video and audio cables, try swapping them out for new ones. You'd be surprised how often cables that work fine with one set of gear suddenly cause problems when a new device is added to the mix. Also, see if the diamond pattern is minimized if you change over from S-video connection to RCA coax connection: often the "sharper" S-video connection is more subject to interference issues.

Try plugging the power cords of the VCR, digitizing device and TBC1000 into an AC line conditioner like an ISObar. Especially during the summer months, high demand leads to unstable power quality which can show as image problems in video gear.

Of course theres a small possibility your TBC1000 is broken or defective, but its very unlikely. Of the consumer-accessible TBC options I've seen, the TBC-1000 has the best quality control and is very well built. I haven't heard of a defective one in five years, but certainly anything is possible especially with second-hand stuff. Short of sending it back to DataVideo for testing, I'm not sure how you could determine if it was defective.

[lordsmurf]

Composite or s-video?

That's moire noise.

[andrewjameshoward]

Thanks for giving me the word herringbone which gave me another googling avenue. Sadly another blind one!

There is no TBC in my VCR. I'm using the RCA connectors on both input and output, output is to an ATI AIW break-out block. I tried the S-Video route and couldn't get a decent signal. I've experimented some more and found:

(i) Without the TBC, these patterns can be found, but the TBC seems to accentuate them. Perhaps it's just making them clearer!
(ii) I've tried different power source, different PC (with another ATI card) and different capture software (Virtualdub vs MMC).
(iii) It's not confined to one video or type of video. Most prone to it are reflective surfaces, often light off faces.

I understand a Moire pattern to be interference between 2 fine lattices. Is Moire noise the same? So one lattice could be the capture sampling pattern, whatever that is? But where is the second? I thought Moire patterns arose when videoing houndstooth check suits. So what's causing this one?

If I cannot isolate the cause then what would be the best way to try to remove the effect? I have researched "moire" in video (loads of stuff for removing it from stills) and found a mention of Gaussian Blur in Sony Vegas as a cure (I don't have SV). Also see that someone has produced a Gaussian Blur filter for Virtualdub. Haven't tried it as yet. Grateful for any other leads.

[jagabo]

A dot crawl filter may get rid of it. Post a small sample clip.