From time to time I see old videotape clips--sports events, mostly--rebroadcast on television, and the images are invariably blurry. Did it look that way when they were originally broadcast, or does the image quality deteriorate over time?

Some of the early recording gear was not made to record the full signal, and some tapes were played too many times before being copied to a fresh tape, disc, hard drive.

Machines used to play them may contribute issues too.

So if I understand right, the picture quality does not deteriorate just because the tape sits on a shelf in a vault for a long time.

If it is stored in the kind of environment you would want to live in than the tape should last indefinitely. Tapes can start to have chemical issues though. For instance the early prosumer EAIJ fromat tapes tend to have an issue with the glue that holds the magnetic particles to the tape degrading and making the surface of the tape too sticky to run through the decks. These and some of the 2" quadraplex tapes need to be cleaned before playing or both tape and deck will be damaged. After cleaning these tapes will be just as good as new.

As a further example of taped signal not degrading take the few surviving reels of pre-WWII, and post war paper tape. These will still play with the same sound quality as when recorded decades ago.

I even have several spools of recording wire with material from the 50's that still sounds real good.

About the only thing that will damage the signal of a tape recording (short of mutlating the the tape or recording over it) is to expose it to a strong magnetic field (an AC field or a DC field can both do similar harm if strong enough).

Sorry, what does prosumer EAIJ mean?

EIA-J was an early 1" reel to reel video tape format. Keep in mind that older footage was shot with tube cameras, which weren't nearly as sharp as today's modern CCD based cameras.

Please read this link for more background: http://www.videointerchange.com/vintage_video1.htm#Vintage%20Video%20Quality%20Iss ues

Further down, he remarks that the best TV for vintage video viewing is around 17 inches in size.

OK, thanks for sending that along.

Reinhart,

It is a regretable history of archiveing with formats at hand at the time as they thought to save the programs for possible replay later. They did archive but diluted the quality each time as the archive formats were lesser specs than the originals every time.

Kinescope film copies are for another time.

In the beginning. The old quad (2") tapes recorded a fairly good representation of the cameras of the day but "garbage in...garbage out" did apply to those recordings. Cams so so, recording good. I would love to see a quad recording of a modern analog camera but that train left the station. And the quad tapes were expensive so as other formats came along, copies were made to archive and free up the quad tapes (and storage space) but the new formats were lesser quality by large jumps.

EIAJ was the first. BW at first and then color through the late 60's to the mid-70's and not usually a broadcaster archive format. 3/4" color cassettes were next in broadcasting in the mid-70's that the broadcasters used daily. VHS and Beta take up the rear at the time but not in broadcasting as a rule. Just some lucky recordings that have survived by engineers and collectors. 1" helical came along just in time in the late 70's and may be the best of the archives if copied from the original quad.

And then there is the deterioration of all of these tapes in these formats which can strike any of the tape formats.

What we see today is more of a circumstance of good fortune that the tape survived and still plays many generations of copying later.

I've got some EIA-J B/W recordings from 1969 that look good. Same for color, except for a bit of 'smearyness.' I've got some U-matic cassette recordings from 1972 that look good today. I agree about the camera issues. They did look kinda naaasty.

Sometimes, I think modern TV adds problems to old video just to help get the point across that this is OLD video, and not the quality of today... whatever that is...

I've seen some kinescopes that were beautiful.... some.....

As a further example of taped signal not degrading take the few surviving reels of pre-WWII, and post war paper tape. These will still play with the same sound quality as when recorded decades ago.


I have never heard of paper tape before. Can you tell me a little more about it?

I've never seen paper tape, but I understand they used it before they figured out how to make mylar and acetates. I have a picture somewhere of an early tape recorder with a spool of paper tape with a magnetic coating. Somewhere.

Stereorob posted a thread about a reel that he has and played reciently. I've also seen it mentioned on the history channel a couple of times.

How many generations of copying did it take until a VHS tape become unwatchable/useless ? 4 or 5, IIRC...

Hello I have beta tapes back from the mid 70s from our local tv station channel 6 the picture looks real lite when played but is still wacthable maybe it is due to the age of the beta tapes, What do you think?

How many generations of copying did it take until a VHS tape become unwatchable/useless ? 4 or 5, IIRC...

I've got Gone With The Wind recorded on Beta from its first regular TV airing on NBC. It looks kinda lifeless now, but still plays. I'll look and see if it is lightening up.

I think 4-5 is about it. I've some 3rd generation things. Not pretty.

I know I've gone as far as three maybe four generations of copying in the VHS format, and despite tons of garbage getting in each time they were still rather watchable (though using a video stabilizer during dubbing would have helped greatly).

I'd bet that with a good stabilizer during dubbing, tapes without bad sections (I often find one or more spots on a VHS tape that will play back with a noise streak even after the tape has been recorded over! :eek: ), some type of filter to prevent line noise from getting to the decks, a metal cage around the equip to prevent pickup of STRONG RF noise pickup, properly functioning VHS decks and a procedure of maticulously checking a copy for flaws (and rejecting flawed copies) before copying it again one could probably get a VHS tape to remain watchable out past 10 generations of copy (probably even farther for S-VHS-ET recorded VHS cassettes).

I don't think the VHS Overlords ever thought we'd be tryin' to save our Stuff..

I know I've gone as far as three maybe four generations of copying in the VHS format, and despite tons of garbage getting in each time they were still rather watchable (though using a video stabilizer during dubbing would have helped greatly).

I remember seeing a show called The Secret Life of Machines, a British series that examined the history of everyday pieces of technology: washing machines, sewing machines, refrigerators, etc. I remember there was one episode magnetic recording, where they showed how audio tape may be made with Scotch tape and rust: take a piece of Scotch tape, rub it in a pile of rust powder, shake off the excess, then run it through a reel-to-reel tape recorder. The message they recorded was "this recording was made with Scotch tape and rust," which didn't sound bad at all when they played it back.
They also talked about video tape, and how the image quality of a video cassette--I don't recall if it was VHS or Beta--degraded very quickly as one tape was copied to another, which was then copied to a third. By that point it was just possible to see the image--a BBC 4 ident--but a fourth copy yielded no recognizable image at all. They explained why this was, but it will come as no surprise to anyone here that I didn't understand it...

I find the image quality on some old home movie Beta tapes I recorded back in the 90s, the quality of the image looks as good as the day they were recorded.... I find that tapes will last much longer than DVD's and CD-Rs... #1 the simple fact that the tape is completely protected by the cassette shell, unlike DVD and CD where even oils from your skin is harmful. I'm a Disc Jockey and I handle discs alot, and I see on these cheap CD-Rs where the oils has deteriorated the disc on the sides, and even some spots on discs where you can see seethrough holes in the material of the discs.. Believe it or not, the "Disk" technology is on it's way out.. I can see even those flash memory sticks are going to be a BIG way of storing audio and video, Even the new TVs these days are being made with USB ports.. I remember those days we disc jockeys used those, what the new generation calls "those BIG black round things", "Vinyl" which Disc Jockeys abandon, believe it or not, not too long ago back around 2005, 2006... And Vinyl even holds up much better than those CDs.. Now a laptop and a $400 DJ program which comes with gear is all we need, as disc jockeys are now starting to abandon CD...

The problems with small analog video tape formats are these: The color signal is recorded very low resolution (heterodine color), the signal to noise ratio of the recording is barely acceptable for the original first generation recording, the time base of the recording is unstable, and barely acceptable on first recordings, and the errors are exaggerated on dubs (severe flagging at top of screen). Just try viewing a second or third generation VHS dub on a TV made before home video became possible. Later TV sets were designed to somewhat compensate for the time-base issues. Oh, and the average unit, VHS, Beta, U-Matic only resolves about 220-240 lines of resolution, which was barely good enough, considering the potential video could have 440 lines of resolution.

...They also talked about video tape, and how the image quality of a video cassette--I don't recall if it was VHS or Beta--degraded very quickly as one tape was copied to another, which was then copied to a third. By that point it was just possible to see the image--a BBC 4 ident--but a fourth copy yielded no recognizable image at all. They explained why this was, but it will come as no surprise to anyone here that I didn't understand it...

Don't know what explanation they gave, but part of the problem was that home tape formats had very strong edge enhancement to attempt to make up for the lack of real frequency response, plus noise coring to eliminate tape noise, which also also would lose any low-contrast fine detail. Proper copying decks would turn off this enhancement stuff to try to get a copy as close to the first generation as possible. Otherwise, you'd increase the overdone edge effects on each generation.

Edit: Plus the multiple stages of noise coring and the ever decreasing chroma frequency response would smear everything into looking like a flat area with outlined edges, sort of a smeary "paint by numbers." Also, home formats used comb filters to separate the adjacent track signals and the "color-under" signal from the luminance, so there was increasing vertical smear of the color also as you went from one generation to the next.