A format made completely for enthusiasts, like the having the whole marathon of Star Trek, Star Wars, into a single disc, or at least 3 movies at once, or maybe a 4k or 8k version of each but again for enthusiasts of physical media only, not a single stream in sight.

The analog part of the Laserdisc is of course disregarded for this in favor of digital encoding.

Pretty easy to calculate - data area of a bluray is about 9,000mm2, a laserdisc is about 70,000mm2. So about 8x as much. So 200GB for a single layer, 400GB for a dual layer. More if you used the more modern 4K disc format (they increased from about 25GB to 33GB for single layer, and allowed triple layers), so up to 800GB.

Realistically if they were to create a whole new disc format, there would be further advances in the data density. There are petabit-scale discs being developed from a while ago (standard disc size), I doubt they'll go anywhere though.

Blu-rays are 120mm radius, Laserdiscs are 300mm. So a Laserdisc has 625% as much surface area as a BD. Excluding the hole in the middle and the safety boundary at the edge, which will remain constant in size and are not part of the usable storage area, I'd expect you could get six times as much data on your notional LaserBlu if all else remains constant.

I do think that it's time we just started archiving this kind of thing and visually appears to be the way that would work for vinyl and optical media.

You can already scan in an LP at sufficient resolution and software will convert it to a "perfect" audio file.

We could do the same with CDs, DVDs, BluRay and Laserdisc without needing lots of different and complex technology... just a scan in the right wavelength of light and some software.

Obviously magnetic media is a different ballgame.

I'm surprised someone hasn't made a device that can do that and sell it, though.

Perhaps not quite.

I vaguely recall the magnetisation of typical media changes the polarisation of reflected light so it might be possible to optically scan a shagged out DDS/DAT tape (or even a dodgy compact cassette with your ZX80 programs on it) and store it for posterity.

I think Sony magnetoptical drives might have used this property.

Panasonic PD did it too. Read with laser, write by heating with laser, set magnetic flux with a 2nd magnetic head.

The technology packaged to do this is is the most practical way. CDs, for instance, using ¼λ deep pits could be read using interference contrast optics without needing a laser light source (the laser is needed because the optics used in CD/DVD players need a longer coherence length) but you then need a mechanism and software to rotate the disc, keep it focussed, record the image and interpret it to create the data file. Alternatively you could just rip it from an ordinary CD/DVD drive.

The archival problems are

1. preserving the data once you've got it - copying from one medium to another as media become obsolete and maintaining multiple, geographically dispersed copies against disaster and

2. being able to usefully interpret the data file in the future.

> "You can already scan in an LP at sufficient resolution and software will convert it to a "perfect" audio file."

Can it? As far as I'm aware, grooves on vinyl LPs aren't simply a one-dimensional waggling from side-to-side but also include a vertical (depth) component, at least for stereo. Not sure about mono discs, maybe it works for those? (*)

But yeah, as Doctor Syntax said in their reply above, unless there's a compelling reason otherwise, the best way to archive most media is via the method they were originally designed with in mind.

(*) Even those laser-based turntables for vinyl records which *sounded* like they should be a great idea when first I heard about them turn out to have major problems if the disc isn't kept scrupulously clean, since even the tiniest specks of dirt or dust- ones that a physical needle would push out of the way with barely any effect- register as highly distracting noise.

If you imagine the groove as a two-sided valley, L audio is encoded on one side of the valley and R on the other (but out of phase? Mono is just side-to-side). The needle now moves both left-right and up-down, depending on the correlation between the two sides but the audio is easily extracted using sensing coils (or whatever) set to be perpendicular, one to each side of the valley. From what I remember they are not quite perpendicular to each other (90 degrees) so there is some crosstalk which is probably why stereo separation on LP is something low, like 30dB?

I think with archiving, the best idea is to take the very best copy you can using the best technology you have available, and work with that, but keep the original as carefully as possible in case better recovery techniques come along in the future.

M.

Of course the bet way is to go as far back as possib;e up the chain towards the original mix. If all you're left with is a collection of pressings - especially from the shellac era - the besst way of dealing with them would be to digitise several and then synchronise them to eliminate outlying samples (scratches and dirt and average out the rest. It struck me back in the day when we were looking at the statistics of matching dendrochronology measurements that it should be possible to synchronise audio recordings in the same way.

Although Shelby got images from both a LaserDisc and a CED, the credits from True Grit are from the CED, not the laserdisc.

The laserdisc credits are from "The mind's eye" ;)

True Grit was found as a bare disk inside his player, and as it wasn't able to be removed normally as the caddy and tray were missing, Shelby was happy to look at that disc under the microscope as the damage to it means it will never be put into a player again.

Note for those who (like myself) haven't had time to watch the video yet, since the article itself doesn't mention CED at all... [1]CED ("Capacitive Electronic Disc") was a different format that actually used a disc (inside a cartridge) with a physical groove traced by a needle- in that respect, like a vinyl LP (but much finer), although the details of how the signal is read are slightly different.

[1] https://en.wikipedia.org/wiki/Capacitance_Electronic_Disc

Yeap, CED the needle is just a guide for the heat, unlike a record, where the needle is the reading head.

I get to cheat with the video, in some shots you'll see Shelby's chat overlay to the left side. And sometimes you'll see my messages in there ;)

Was slightly disappointed to see that although the latest Gorillaz release, a short film, was touted as being "online (& Laserdisc)", the Laserdisc doesn't seem to be available in the [1]official store .

I do have a working Laserdisc player. Must clean the lens again. The Empire Strikes Back , which we watched over Christmas, was a bit grainy.

To answer a question in the article, Laserdiscs had several types of sound. Early ones were FM analogue. Later ones were 16 bit 44.1kHz stereo (often Dolby Surround) or 2x mono (for dual-language releases), but while NTSC discs retained the analogue tracks*, PAL discs had to use the space for the digital sound. Later again, NTSC discs lost the analogue audio tracks in favour of AC3, which normally had to be decoded external to the player. PAL discs could either have 16 bit stereo or AC3, not both. I believe nearly all PAL discs opted for 16 bit stereo.

M.

*NTSC used (simplifying) less "space" for the video signal than did PAL. As I understand it, the lower frame rate of PAL meant the discs could play for slightly longer per side, but the higher bandwidth for the video signal meant that there was less "spare room" in the signal for additional stuff like audio.

[1] https://store.gorillaz.com/gb/

I have non-working original LaserDisc players awaiting a future restoration project when I intend to replace the gas laser with a modern semiconductor one. Probably won't happen! Also a working original CED SelectaVision player.

The thing about the laserdisc players is that they're *massive*. And very heavy, delicate, and extremely analogue. But the CED player is much simpler - there's hardly any electronics in there. But the discs are contained in a plastic sleeve and extracted when you put them in the player, meaning the disc itself is delicate.

I feel that if the laservision system had been able to record, it would've survived the competition from videotape.

Possibly. However, IIRC, one reason why VHS won instead of the technically superior Betamax is because VHS had porn and Betamax didn’t; the no-porn on Betamax was because of a decision by Sony higher-higher. Pornless recordable LaserDiscs might have made things difficult for Betamax; the last major market for Betamax and derived systems were professional audio-video people at places like TV stations and the like, the techs liked the superior abilities and weren’t (offically) playing porn at work. A high-end recordable LaserDisc system would have been quite nice for the pros, as apparently the picture quality was superior on LaserDisc. Especially after the tapes got a bit of abuse, which absolutely would happen. Recordable LaserDIscs which had porn would compete, seriously, with VHS. A major reason for DVD’s success was because of the flood of porn on the format (Sony learned from Betamax, or at least listened to Phillips); already existing LaserDiscs would have competed there, too.

Many years ago I had a LaserDisc player and a VHS recorder. One of my projects was making a copy of a LaserDisc movie (Star Trek II: The Wrath of Khan, a.k.a. The Best Star Trek Movie Ever Made) onto VHS. The picture quality of the VHS simply didn't compare to the quality of the LaserDisc. Possibly this was due to the method I used to make the recording, but I doubt it. Recordable LaserDIscs would have been... interesting. And probably expensive. I remember how expensive recordable DVDs were when they first came out, this would have been at least as bad.