VHS playback: contrast lines extend, smear?

[packsnap85]

I have noticed an issue with a few VCRs that I have, that I don’t know if it is a VCR quality issue or something that can be improved with better alignment. The best way I can think to describe it is using the example of the Texas flag, with two horizontal fields of contrast butting into a vertical field. With the issue I am having, the contrast extends beyond the bounds of the horizontal fields and into the vertical field. This is most noticeable in darker scenes, where say a piece of white paper is sitting on a dark table and a face is in front of them in the scene, and the contrast between the paper and the table extends and becomes noticeable for some distance into the face. It is possible I just haven’t found the correct terminology to describe what is happening. Any help would be greatly appreciated.

[timtape]

Hello Packsnap85. "A picture is worth a thousand words". Why not upload one?

[packsnap85]

Example photos attached

[lordsmurf]

Chroma or luma smear.

- crappy VCR is likely, what are you using?
- bad recording also likely, especially nth gen

[packsnap85]

Those particular images are from a JVC 5902 fed through a Panasonic ES10. I have seen similar with an MV55 combo player as well, along with others. My best results in low light scenes like this have come from a JVC hr vp59u through the ES10. Some questions on my mind:

Why does the lowest end vcr I have produce the best results here? Is it that it has been kept in the best condition through the years?

Does tape path alignment have anything to do with this?

What other components of the vcr could be blamed?

[lordsmurf]

It's the tape recording itself. You can attempt advanced Avisynth to reduce it, but it'll always be there.

Again, it looks nth gen, not a master recording.

[packsnap85]

Thank you. I am not familiar with the nth gen terminology. The tape was the original tape of a home video from the late 80s.

[latreche34]

Can you post a full frame, Those crops could be very small and the effects are blown out of proportions, VHS is not perfect, scanning has a delay and will always result in smear, So how big those areas you posted are compared to the full frame? Some ghosting could be source related, either from the original program or a low end recording VCR.

[packsnap85]

They are between 1/4 and 1/3 frame height and 1/3 and 1/2 frame width.

[RobustReviews]

Could be a few things.

Could simply be a lousy recording, or a wonky machine. Remember this, I imagine, was made on a domestic 1980s machine.

As it occurs at the areas of highest luma (brightness) contrast this usually points towards either cabling (now, or of course, back then) causing issues with the signal during the fastest rate of change. I will say though, normally (but not always) this causes a reflection ('ghost') that decays exponentially, but there's little reason to say it can't cause all sorts of maladies. I've seen some bizarre things.

Unless you're current playback deck is of astonishingly low quality (they're out there) or has impedance faults, it's unlikely to create its own reflections.

My diagnosis would be to just play a known good tape through television, if the machine is creating them on one tape, it'll very likely create a similar flaw on all tapes. I don't know how you connect the machine but try either a different method (composite to YC or vice versa) and see if they diminish.

Cabling might be an issue, although I'm not convinced at the moment.

That said, I don't know how tightly cropped in your images are, recall VHS ultimately does just have very poor chroma reproduction and this might just be a case of an old VHS doing what an old VHS does.

[packsnap85]

Thank you for the response. A couple observations from playing similar scenes across multiple VCRs and viewing on a monitor:
-it seems the phenomenon is there in all VCRs to some extent.
-the 5902 and 59u models seem to be on opposite ends of the spectrum as far as how noticeable it is, with others falling somewhere between.
-the 5902 model, which shows it the most, seems to have the highest contrast and most saturation

Is this something that could be made better or less noticeable by adjusting playback levels, and clipping less of the high brightness areas? Post capture levels tweaking doesn’t seem to help, but I am curious as to if an internal levels adjustment would act differently.

[latreche34]

Depends what setting you have on the VCR, Like 3DNR known to sharpen the edges of the video.