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by Gordonjcp 1054 days ago
It's a shame the first youtube link is so overcompressed because it's clearly been from very clean VHS, and absolutely destroyed when it was encoded.
1 comments

There is no such thing as clean VHS. VHS is roughly youtube's 240p quality.

Also the first video has 1440p options on youtube so why do you think it's compression giving bad quality? This is about as good as VHS gets. I think most people don't remember how bad it was on tiny CRTs.

That video is compressed to hell, it looks like a QuickTime or something from the 90s. That someone upconverted it to 1440p on YouTube is inconsequential. You can see the square MPEG blobs ferchrisakes!

Here is a dirty VHS with dropouts which looks WAY better:

https://youtu.be/ZlsS_a4qdI4

> There is no such thing as clean VHS. VHS is roughly youtube's 240p quality.

And yet if you IVTC a film telecined for reproduction on VHS using 3:2 pulldown you end up with the full 480 lines at a rate of 24fps.

Furthermore, if you consider the ~3MHz in luminance bandwidth, you get ~240TVL which works out to ~320 "pixels" per line at the NTSC DAR of 4/3.

Chrominance bandwidth and analog noise notwithstanding, I'd say that ~320x480 is a fair bit better than "240p".

And, for the record, VHS sucks. It just doesn't suck as much as you're claiming.

Finally, Laserdisc FTW.

VHS is about 240 lines horizontal resolution and 40-50 lines chroma resolution.

Even at 1440p the video has massive MPEG blocking, it's been heavily compressed after being captured off tape. VHS has not got MPEG-like compression.

https://www.youtube.com/watch?v=8K8dUkeDZTM is an example of a badly-worn and therefore extremely "speckly" and dull VHS tape that I captured a while back. Youtube has a hard time with the chroma noise, but I didn't want to overcook it with denoising etc. so I just left it as it is.

Notice how much smoother everything is?

https://www.youtube.com/watch?v=ZPmCygZIjio is a capture of a very damaged Sony 8mm analogue tape, again with a lot of dropouts. Notice how there's no MPEG blockyness?

These aren't even especially good captures, and were done off a not-properly-set-up "industrial" VHS machine which desperately needs realigned (and probably new heads), into a DV camcorder used as a DAC into a Firewire card.

Degradation of analog data stored on magnetic tape is a lie—teach the controversy!

For real though, can't one just... not post about stuff you don't know about?

If one wants to give one real information one should feel free to link one of one's sources. Try this one.

https://www.freevideoworkshop.com/whats-the-difference-betwe...

The thing you have linked to is correct, but you're reading it wrong.

VHS has 240 *horizontal* lines of resolution, meaning that a grid comprising 240 alternating *vertical* black and white stripes ought to be resolvable as a bare minimum. This corresponds (roughly) to 2.5MHz of luminance bandwidth. This is also confusingly named, but there you go.

Youtube's 240p resolution is lower quality than VideoCD, and far *far* lower quality than even fairly manky VHS.