How can I remove vibration from old videos when capturing???

[funkydude74]

Hi all. I've been capturing old video recordings I transferred from vintage 1970s Philips N1700 VCR cassettes to PC (The UK members might be familiar with this format). Anyways a number of the VCR tapes I transferred to VHS the picture looks great but vibrates horizontally. And when I capture vibrating video on PC the vibration is magnified which spoils the picture when viewing it on DVD as the vibration looks excessive. Basically my take on the vibration problem is that one field is displaced slightly to the right of the other field causing the picture to vibrate. Just wondering is there anyway (apart from buying an expensive timebase corrector) to record vibrating video on PC and getting rid of the vibration using some program?

Cheers
Troy

[Sugar]

It sounds like your capture card inversed the field order. Did you change is was top field first when you captured. I seem to recall having read that analog video was top field first as opposed to dig video which is bottom field first.

[BrainStorm69]

I would try reversing the field order as Sugar suggests. If that doesn't correct it, then a TBC is probably in order.

[racerxnet]

Are you sure it is not the tape itself? If all that changed is the tape and the picture vibrates then I would suspect the tape. This is do to the surface of the tape being to smooth and sticking to the video head. This in turn leads to a shortened head life due to the tape/head contact. All modern heads have a 19 micron head with machined grooves to create a cushion of air between the tape and video head. The air gap is about .0015 thousandths of an inch. Tape thickness also plays an important roll in conforming to the head.

[funkydude74]

Hi all, thanks for trying to help me. Just have to clear a few things up. Firstly I'm having no problem with the field order, I always use field order B as field order A doesn't work.

Secondly yes it is indeed the tape that is the problem, basically I'm transferring really old 1970s and early 80s Philips VCR tapes which when played some play without horizontal wobble, some play with horizontal wobble as they happen to be maybe a little sticky and when transferring these tapes to VHS, what I see is what I get.

However when I record from the VHS copy to PC, on playback the wobble is magnified so whilst on the original Philips VCR tape and VHS copy tape the wobble is as is, the computer recording which I put to DVD wobbles twice as bad.

Anyhow just thought there might be a program that can align the fields or displace the odd or even fields closer in line with each other to reduce excessive horizontal vibration.

Cheers
Troy

[SatStorm]

The only way to correct this jumping is through filtering. Unfortunatelly, in this case there gonna be some picture loss or some motion blurness

You have to play with filters based on time axis corrections. Like temporal smoother. And we talking about heavy filtering here...
Also, you can try a filter called "frame merger". It might work for you (it works for me on plenty cases...)

An advance alternative is to seperate fields, use frame merger on them, join fields, add a temporal smoother in a logical value (3-4) and save to a new avi. You can do this with virtualdub and probably avisynth.


Also try to discard one field. It works sometime, but then you have for a source a VCD framesize (352 x 240/288). For PAL it might look ok (VHS like) but for NTSC gonna look bad....

[lordsmurf]

You could get a TBC

... or try a restorative deinterlace (adaptive on the odd field)

I prefer TBC first.

[SatStorm]

No no, I know this kind of jumpin (If I guess right from the description...).
It's something TBC can't help, neither a reconstruction of the progressive source can help....
This "jumping" is not because of tape degration or a taping from a bad transmission, or whatever. It mostly happens because of faulty mechanical parts of the VCRs. On the same VCR those tapes plays perfect, but on all others no.
So a TBC here won't help. Only software filtering...

[racerxnet]

To Satstorm,

If you read my post it is the tape itself causing the jitter in most instances. A TBC cannot correct the tape sticksion to the head. Nor can the servo system corrrect this situation fast enough while there is tape to head contact. Most mechanical problems manifest as ; lower tape edge crinkle, no rewind or fast forward, tape will not insert, poor playback due to head wear on the tips, improper tape path alignment, etc.
If it is all tapes I would suspect you are correct, but reading into the posts suggest it is with specific tapes.

[SatStorm]

Either way, the only way I know to suggest for "correcting" this "Vibration" is through filtering! And I'm not talking here for noise filtering: I mean time axis filtering, like this "frame merger" one.

The theory here is that if 5 fields compared and one of them is the jumpin one, the average gonna bypass it..

[dphirschler]

If it is the tape sticking, you could always try coating it with some sort of lubricant. I don't know if this tape will behave the same as reel to reel tape, but I think there is some lubricant you can use which is made for reel to reel. Worth a try.


Darryl

[johns0]

If you use lubricant on the spinning head drum the tape will spew out and wind around the drum a million times,same as cleaning the heads with alcohol and not waiting for it to dry before putting a tape in.A good quality vcr is what you need to play tapes that wobble and stick.

[funkydude74]

Hi all. Thanks again for your suggestions. Frame merging sounds like a good idea when it comes to recording progressive scan film style material from these tapes eg. movies but when it comes to video style material such as studio TV shows merging the frames will give them movie style motion instead of fluid video motion, that's if you mean by merging frames as blending them into a single progressive frame.

Anyhow in case you's are wondering what I mean about the Philips VCR format here's some pictures below showing this format:






The layout of the tape is similar to the American AVCO Cartrivision format of the early 1970s. Anyways the Philips VCR format pretty much lasted from 1972 to 1980. The pictures shown above are from a British vintage TV/VTR collector's site http://www.eclipse.co.uk/mikey/n1500.html . I have 6 VCR format machines including the ones in the pics above which you'll see 5 of them on my website at http://70scountdown.50megs.com/philips.html .

Anyways it's like anything with really old videos, it is expected some will transfer good and some will transfer bad. White or black dropout flecks in pictures of old tapes are common due to I assume metal oxide shedding, they're no real drama but tape sticktion is a real bloody pain in the arse as they can be impossible to rewind and the picture can wobble and skew really bad, not to mention wear and dirty the heads.

Cheers
Troy

[lordsmurf]

My TBC-1000 has removed jitter MANY DOZENS of times from tapes I'd almost given up on proir to my TBC purchase.

[SatStorm]

This "frame merger" virtualdub filter I mention, is not exactly frame merger... It also compare fields (5+/-) and when a field is off the average, replace it with the compo of +/- 1

If I guess right, I believe this is the only thing you can do, beyond TBC.
TBC might help you capturing all sort of fields/ frames and make it easier for this filter to "correct" this problem. But I don't think that it gonna help you really on the "vibration" thing. It might help you capturing without field / frame drops this "vibration" on PC.

Of course I only suggest here, since I actually don't have access to this tape so to test it myself! There is always the chance to be non correct...

By the way, and sorry for this, could you help me in this off topic subject?
https://www.videohelp.com/forum/viewtopic.php?p=815151#815151
I had a HD disaster and I need help!

[racerxnet]

If i am correct your Phillips uses a coaxial or stacked cassette tape. This type was used by Phillips and Grundig prior to the Phillips System 2000. Checking the back tension might help with the vibration.

[davideck]

This sounds like classic timebase error to me. Copying one tape to another without a TBC inroduces even more time base instability. I too have noticed that dubbed tapes are more unstable than first generation recordings. The reason that it looks worse after you capture is because your capture card cannot track the instabilitites as well as your monitor.
The JVC VCRs with built in TBC provide exceptional horizontal time base correction; better than even my FOR-A professional TBC.