Macrovision on domestic VHS recording?

[Gibson's Squares]

My friend has asked me to make a DVD copy of a VHS tape, but my DVD Recorder is refusing, saying the tape is protected.

The tape is a bog standard domestic E180 from 1995 and is a second generation recording of a home-taped Channel 4 (UK) broadcast. (It's second generation because he just left the VCR recording, then dubbed the main portion he wanted to another tape and cut the adverts out - all done back in 1995 or a little thereafter.)

I'm not sure why I'm getting a problem - was Macrovision ever broadcast as part of the TV signal?
Or could his dubbing have somehow introduced Macrovision? I don't remember VCRs coming with such a feature?
Other portions of the tape (different TV broadcasts) copy without problem.

I've used my DVD Recorder on 100s of old tapes and never encountered this before.

[BTW I know how to solve the problem, I have a seperate chain I can record it through, I'm just trying to learn why and how it got there!]

[redwudz]

Just a guess, but some VCRs/DVD recorders have a problem with 'false Macrovision' detection where noise on the tape causes it.

Though with your VCR/recorder, you should have encountered it before with other conversions.
I don't believe Macrovision was used with broadcast TV, but other members may have better information.

[showtaper]

It seems to be a false positive, I get them occasionally. Macrovision is random information placed in the blanking interval of the television signal (simple explanation) which fools the AGC circuits of most VCRs which prevents VCR to VCR copying. Most DVD recorders recognize Macrovision and refuse to record and display the "protected content" message.

If the content had been broadcast with Macrovison encoding, the original recording could not have been made.

I have several "black boxes" which rebuild the blanking interval which eliminates the Macrovision and helps stabilize the signal. My old Videonics MX-1 digital mixer removes Macrovision as well.

If the OP is using an all in one VCR>DVD recorder one suggestion would be to try feeding the DVD with the output from a different VCR.

[jagabo]

second generation recording

Yes, almost certainly false Macrovision detection. Poor time base of VHS compouned by a second generation recording causes Macrovision detectors to kick in.

[Gibson's Squares]

If the content had been broadcast with Macrovison encoding, the original recording could not have been made.

Ah, of course. Makes sense.

It's so weird it's just this one recording on the tape that's giving the false positive, there's plenty of other recordings on it made with the same VCR setup and all are trouble free.

UPDATE: I've used my TBC and a different playback VCR and I absolutely cannot get my DVD Recorder to record this section of tape. Is it possible for whatever is causing the false positive to still leak through a TBC?

[jjeff]

A TBC should allow you to record basically anything.....what kind of DVDR do you have? Some are more prone to false CP but again a TBC should be able to remove any such CP
LGs and later Sony DVDRs were notorious for false CP, I've never had such issues on my Panasonics but of course they won't record a commercial source with CP without a TBC or Sima/Grex type of device.

[JVRaines]

A lot of different hardware goes by "TBC." What you really need is a frame synchronizer that replaces the vertical interval with fresh signal.

[Gibson's Squares]

A TBC should allow you to record basically anything.....what kind of DVDR do you have? Some are more prone to false CP but again a TBC should be able to remove any such CP

Recording to a Panasonic DMR-EZ48, via a Datavideo TBC-1000.

A lot of different hardware goes by "TBC." What you really need is a frame synchronizer that replaces the vertical interval with fresh signal.

I think the TBC-1000 does that?

I've got a Toshiba DVD Recorder too which I'll try later.

[Eric-jan]

But.... the video connection is never mentioned....... could be important !

[Gibson's Squares]

But.... the video connection is never mentioned....... could be important !

Well the Toshiba also refused to record the tape (also via the TBC-1000).

Lineage involves S-Video cable from the playback VCR to the TBC-1000, and then an RCA/phono from the TBC to a Scart adapter going into to the DVD Recorder.

[lordsmurf]

The TBC-1000 does strip and replace that part of the signal inhabited by Macrovision. That means you have something else going on, not standard false anti-copy detection.

I rarely see this, but it's always from a copy of a copy VHS tape.

The DVD recorder is likely at fault here.