Posted by MassiveProng on 01/23/07 10:04

On Mon, 22 Jan 2007 17:25:06 GMT, bv@wjv.com (Bill Vermillion) Gave
us:

>In article <ii8rp29a07pigd5m63s6vl6tp7d34f82hn@4ax.com>,
>JoeBloe <joebloe@nosuchplace.org> wrote:
>>On Thu, 4 Jan 2007 13:14:17 -0000, "M.I.5?"
>><no.one@no.where.NO_SPAM.co.uk> Gave us:
>
>>>But that would have been an entirely new format. Same size disk maybe, but
>>>a new format all the same.
>
>>
>> You don't get it. All optical disc technologies evolve.
>
>> DVDs right now have different res previews and extras than the film
>>segment, and it peels off the disc at a different bit rate.
>
>> What I mentioned would be no harder than that, and using CLV, very
>>little would need to be changed. DVDs are read at varying RPM rates
>>as the disc progresses. An LD could be read the same way, providing
>>the varying rate and best use of the optical data area real estate.
>
>For the widest majority of LD's produced they were read the same
>way. CLV - Constant Linear Velocity - means the disk speed varies
>according to the place on the disk. CAV - constant angular
>velocity - is the one that rotates at the same speed throughout.

I don't need a primer on the methodologies used in Laser Disc
manufacture.
>
>Technically after the first few CLV disks were released, they found
>that there was a herringbone problem, so while they were still
>called CLV, there were CAA - Constant Angular Velocity.

Absolutely incorrect! CLV and CAV were BOTH available from the
beginning and are BOTH DISTINCTLY different from each other.

The Laser Discs used by the video game industry REQUIRED CAV to get
addressed frame access! "Dragon's Lair" and "M.A.C.H. 3" were
perfect examples of the first.

CAV discs were exactly 54,000 frame, one half hour per side discs.

NASA released their discs this way and I have a "google earth" type
disc from over a decade before you guys could do such a thing online,
though without map overlays or coordinate references.

CLV discs were 1 hour per side, and despite the fact that they changed
the manner they generated the WORM, the disc was STILL CLV from center
to edge, and a laser was STILL unable to pause and read a single frame
over and over again, and the players REQUIRED field frame memory to
accomplish a paused frame.

> That meant
>that there were bands of CAV - that changed rotational speed every
>little bit - so that adjacent frames did not interfere with each
>other as they did in pure CLV format.

Nope. The disc did slowly change speed, but ALL CLV discs did so
from the beginning. What part of CONSTANT and LINEAR do you not
understand? Fats rotational speed at hub and slower speed at edge
were ALWAYS part of the normal operation of a CLV disc. The
improvements you mentioned were NOT a transformation to CAV EVER!

>> The physics are such that the data rate for the outer portion of the
>>disc is capable of a higher data rate than the hub portion, for any
>>given RPM.

NOT AT ALL!

CLV discs SLOWED toward the outer edge. SAME data rate and pit pith
ALL THE WAY THROUGH.

CAV discs held the same speed, HOWEVER, the pit pitch was stretched
as the tracks progress across the disc. SAME DATA RATE.

ONE FRAME per rotation is what CAV means TWO FILEDS. It is visibly
apparent on EVERY CAV disc, and the are EXACTLY 54,000 frames each
side (one half hour). The blanking areas are quite clear upon
examining a CAV disc.

The lineal write density for EITHER disc was EXACTLY the same.

>Correct. And there is also a better way than changing the
>rotational speed - and that is changing the data read/write
>algorithms so you write more per revolution as you get further from
>the center. That is how hard-drives work.

Hard drives are ZONE sectored now, dipshit.

IBM reached the maximum MR head write lineal bit density some years
ago, and THAT is why we are no moving toward perpendicular recording
methodologies.

>> That 12 inch platter would hold 4 times the data at least of a 5.25
>>inch disc. Entire TV series seasons could end up on one disc.

Nope. The 12" form factor has other problems which preclude this
desire. Such as platter flatness. The wobble at the edge of a 12"
platter can be huge in a simple comparison of ten copies of the same
title. The laser head had to have a vertical focal traverse of almost
a half inch.

Today's smaller form factor platters are much easier to stamp out
flat, and use much less plastic, and have much less failure rates at
the stamping plants. THAT is why increasing the lineal bit density on
the SMALLER platters is a much better idea than trying to scale up in
size. The head stays right flat (practically) as the discs are now
much flatter. We have decided to make the increase via a change in
spectrum and track pitch. Works for me.

>And when the CD first came out it was Philips who came up with
>the 12cm size.

No shit. Yellow book.

> Sony had been so used to 12" LDs, and LPs, that
>while they knew they could put audio on one, they did not think
>anyone would want or buy something with 12+ hours playing time per
>side.

You over simplify what took place, and are clueless actually, about
most of it from hat you have written here.

> It took Philips to tell Sony that all they needed to do was
>make the disk smaller.

The industry as a whole knew where they were going.
CDs came out YEARS before LDs did, dumbass.

Pioneer made the LaserDisc, NOT Sony.Sony made discs, but were not
involved with the concept or initialization of the industry. It was
Pioneer's baby (much to RCA's chagrin)

> Typical "can't see the forest because
>of the trees" scenario.

Typical "know it all" who is actually yet another dumb horse wearing
blinders, and a lack of aptitude for technology... as well as the
physics.

Try again, Billy. You read your wikiTard page too fast, and it
likely contains errors from what you wrote here.

>> Thing is, nobody will go back to 12" as there are just too many
>>mechanical anomalies between the hardware and the discs themselves.
>>You thought the yields on BluTurd production runs were bad... 12" is
>>horrendous, and would quadruple with the tighter laser wavelength and
>>track pitch.
>
>The largest problem from my POV was NOT the size but the
>manufacturing process where the sides were plated and then glued
>together.

Today's DVDs are nearly ALL laminated, multi-layer discs, Billy.
They now merely look through one layer to the other, as opposed to
flipping the disc (which still also happens).

> Once you have different materials bonded together you
>have problems with such things as delamination, oxidation, etc.,
>between the different materials.

Oh boy. The kid knows how to read. That was then, this is now.

DVDs are ALSO laminated. The technology has simply advanced, and
THAT IS ALL. They are STILL glass master stamped plastic discs which
get metallized by ALUMINUM, and then get LAMINATED together to form a
single disc.

LaserDiscs had adhesive seepage problems, but that was not what led
to their demise.

> This is where the laser rot came
>from.

No shit, sherlock.

> I have 3 or 4 eight-inch LDs - that required a spacer to
>play them on a standard player as they were only one side.
>
You have a retarded player. ALL of my LD players would play ALL 4
form factors available at the time, with NO adaptation(s) required.

>These were free demos that you could get from Warner Bros.

Whoopie doo. They were likely illegally released discs that were
technically a NON-conformant form factor that was meant for studio
only use initially.

>[as I
>recall] and were made more like large CDs. Just one side with
>a printed label on one side and data on the other.

There were plenty of commercial 8" form factor LD releases. I have
some of them, and they are not studio demos.

>There are think and I suspect in a 12" format they would be far too
>easy to break, bend, spindle, staple, or fold [as the printing on
>bills years ago used to say].
>
>> Maybe we should go back to piano roll methods. That's what a
>>holocube is essentially.
>
>Ah - multi-layer piano rolls. Interesting concept! Manufacturing
>might be a pain though :-)

They wrote ten GB to a roll of shipping tape in Germany over five
years ago.

Holo-cubes may be in your future.

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