Green/Purple color flicker on old VHS

[ragroo]

Hi everyone.

I have a question regarding importing of VHS video through a USB/VCR port (European PAL VHS and VCR).

I've imported several VHS tapes that have been completely fine (of adequate quality for my needs). However this specific tape has some problems during importing. The colors on the video on a large part of the image keeps flickering between green and purple (image part below the arrow on the attached image below). Only a few random scenes here and there are showing normal colors without flickering, put this changes even during the same scene.

I know that the tape has been imported onto VHS from a video camera and later copied between two VCR machines to a new VHS. Unfortunately, I don't have the original VHS however.

Does anybody know what to do to get a proper import or can this be corrected post-import?

[JVRaines]

Probably caused by faulty recording of the I and Q color channels. See the end of the following thread for techniques to fix with Avisynth.

https://forum.videohelp.com/threads/370897-Restoring-30-year-old-Betamax-tapes-would-ap...ate-any-advice!

[johnmeyer]

I remember that thread. Several of us tried to help with techniques for color restoration, but none of us really addressed the issue of how to improve the capture process to avoid the switching between purple and yellow cast.

Things you might try include:

1. Use manual tracking and see if you can "tune in" more stable color.

2. Try using each of the correction circuits in your VCR, one at a time, as well as in conjunction with each other. If this is an LP (6-hour) recording, some VCRs have a setting to correct problems with low-speed recordings.

3. Try the tape in a different VCR, if you have one.

[ragroo]

Thank you for your fast replies.

Regarding Avisynth, will this require to adjust colors in every frame? If so, 4 hours or video would be quite tedious.

Regarding tracking, this might work/make it better, though I don't have that function on this VCR machine, probably since I have no remote control.

I don't know anything about adjusting circuits, probably that also requires a remote control I think that I will acquire another VCR to test things out properly.

Again, thank you so much for the responses!

[TimA-C]

Depending upon the player, you may be able to adjust tracking using the buttons on the front panel. I have a couple of Sharp VHS players that I can do this with even though the buttons aren't marked for adjusting tracking. It may be worthwhile doing a little research on-line. Would a programmable remote give you these options? I don't know how far back the code databases go?

[johnmeyer]

Tracking is often controlled (but not always) by using the channel up/down buttons on either the VCR or remote, while the tape is playing. You then press both channel buttons at once to return to automatic tracking.

Since many later-generation VCRs put all controls into the on-screen menus, you are pretty much sunk if you can't access those menus. Once again, however, most VCRs do have a menu button on the front panel of the VCR and, while cumbersome, you can often set most menu items without using a remote control.

[ragroo]

I found the manual for the VCR (Philips VR 247/13X): http://www.manualslib.com/manual/176648/Philips-Vr247.html?page=4#manual

The remote does have tracking. Now I just need the remote

[TimA-C]

Doing a quick search for "Philips VR247 remote" brings up a number of possible sources . . . ?

Good Luck!

[ragroo]

Yes, thank you. I think that I should be able to find a remote for the VCR.

I've tried troubleshooting with what I've got, and found out that if I manually adjust/turn the wheel slightly, the colors get partially better (more passages without green/purple flickering). Could it be that the tape is not rolled up tight enough? My current VCR have a broken rewind function (it will only rewind while playing), limiting a fast forward/fast rewind.

[johnmeyer]

What "wheel" are you adjusting?

[ragroo]

I'm basically just winding the tape forward manually a few millimeters (i.e. turning the left (front view), white wheel counter-clockwise). Hope that makes sense.

[johnmeyer]

Oh I see: you are using the jog/shuttle wheel to slowly advance the tape while viewing the still or slow-motion video on your monitor.

If this produces different color than what you get going full speed, then it does sound to me like it might be a tracking or alignment problem of some sort. Others here may have some additional ideas or insights into what else you might be able to do in order to capture the original color. Hopefully you'll be able to find that remote so you can experiment with the tracking adjustment while playing the tape at full speed.