DVD laser deterioration?

[William Sommerwerck]

My bedroom DVD player is the original Sony DVP-S7000, which I purchased at
half-price when it was discontinued in 1999. It's given good service, except
for locking up a few years ago, which turned out to be a good thing, because
I bought the then top-of-the line Sony for a ridiculous price. Anyhow...

I was going through a box of Cary Grant films, and "Destination Tokyo" just
didn't want to play (though every other disk, from that set and elsewhere,
was fine). About ten minutes into the film, it starting jumping forwards and
backwards, and sometimes halting altogether. If I walked away, I'd come back
to a blank blue screen.

Naturally, Warners wouldn't replace the disk, because it had been purchased
at retail, and Costco didn't have any more of the boxed sets.

I was looking at another film today, which had one or two "glitches" of this
sort, and it got me thinking. So I popped "Destination Tokyo" in my BD
player -- and it played flawlessly.

I'm starting to think that A: this pressing of "Destination Tokyo" is just a
skosh out of spec, and B: the laser in the DVP-S7000 is starting to decline,
which C: means that I'm seeing erratic behavior.

Any opinions? I'm not trying to start an excruciatingly long conversation.

Thanks.

 

[Geoffrey S. Mendelson]

2) if you've used a "cleaning disk", call it quits and chuck the unit in the
trash; you've probably scratched the lens into a repair that'll cost more than
the price of replacement.

I would not. In some places, here 3000 feet up in the desert, everything gets
covered with a layer of powdery DRY dust. The cleaning disks often fix
optical drives with no problems.

In other places, especially ones with high amounts of hydrocarbons
or humidity in the air, they do just scratch things, or worse, move around
the much.

The last DVD player I chucked was left on all the time, playing the menu of
the disk. The rails that the laser assembly rode on were worn down at that spot.
Since it cost me $30 for the player, and would cost $20 to replace it, I
just gave up.

YMMV.

Geoff.

 

[William Sommerwerck]

if you've used a "cleaning disk", call it quits and chuck

the unit in the trash; you've probably scratched the lens
into a repair that'll cost more than the price of replacement.

I've never used a cleaning disk.

 

[William Sommerwerck]

I was going through a box of Cary Grant films, and "Destination Tokyo"

Bedroom stuff tends not only to end up dusty (fabric dust from bed
linen, clothes, dead skin, etc!) but is generally used less often than
other kit. So, I'd start by opening it up, clean the lens with a q-tip
dipped in alcohol, and clean and relube the sled. You may well be
surprised.
Let us know how it goes.

Well... Everything else plays correctly in this player. I was really asking
for anyone who had experience with deteriorating lasers.

When I have the chance, I'll pop the top and see what's going on.

 

[William Sommerwerck]

Try manually cleaning the laser block optics and making sure the sled

move freely. If that does no good it's time to chuck it or buy a
service manual and retune the tunables. Also possible dry caps in the
PSU causing some dirty DC and incorrect voltages.

Thanks.

 

[William R. Walsh]

Hi!

Any opinions? I'm not trying to start an excruciatingly long conversation.

Well...I don't think you're ready to lose the laser diode quite yet.

I don't know what it is about DVD authoring that is so hard, or where the
quality control problems come in, but I've had a few DVDs that were
problematic in players otherwise known to work. Funny thing is, more often
than not, many of the troublesome discs would be *fine* in a cheap Apex
Digital AD-1201 player.

Go figure. Sometimes I think the movie and TV studios *know* what they're
doing to make these discs have such defects.

My brother was using a 1998 era Matsushita/Panasonic DVD drive in his
computer to watch movies. (Yes, the drive was cheap.) He has used the
daylights out of it and only recently did it just quit reading any DVD.
(Don't know about CDs.) I haven't had a chance to look at it, but it would
not surprise me if its laser had simply worn out to the point where it no
longer worked reliably.

William

 

[Geoffrey S. Mendelson]

Go figure. Sometimes I think the movie and TV studios *know* what they're
doing to make these discs have such defects.

One of the problems is that a DVD is very limited in the format, encoding,
resolution, frame rate. Anything other than the few resolutions, frame rates
etc, are "out of spec".

Here is a chart with the requirments for a DVD:

http://www.mplayerhq.hu/DOCS/HTML/en/menc-feat-vcd-dvd.html

HOWEVER, a modern DVD player will play almost anything, as long as the internal
decoder (hardware or software) will play it. Most computer programs will too,
except earlier versions of Microsoft Media Player for Windows. It would play
files of almost any spec, but if it was playing a DVD, it would only play
ones within spec. I have not tried it in years, but I expect that limitation
is long gone.

I have not seen one in years, but when DVD players first came here (around
1998-1999) the expensive Japanese brand ones were very finicy about the
format of the disk, the zone, how it handled NTSC (24/10001 and 30/10001 frame
rates) versus PAL (25) and so on.

The cheap Chinese ones had set up options for TV type (NTSC/PAL/auto) converting
frame rate as needed, and were not very finicy. If it was an MPEG-1 or MPEG-2
encoded file, it would play it.

Maybe the disk is slightly out of spec in encoding. The only way I know how
to tell is play it with mplayer on a Windows or Linux system and look at
the console output. It will tell you the codec used to decode the video
and audio, the frame rate, the bit rate (how much data is used for encoding),
the resolution etc for both audio and video.

Note that some combinations such as MP3 audio with anything, or MP2 audio
on NTSC disks are not "legal" although modern players will happily play them.

Geoff.

 

[Mark Zacharias]

Thanks.

I would try cleaning - and note the 7000 has TWO laser lenses in a common
housing.

It's old enough to have picked up a layer of dust in there.

Also worth cleaning that particular disc - you never know...

Mark Z.

 

[William Sommerwerck]

Go figure. Sometimes I think the movie and TV studios *know*

One of the problems is that a DVD is very limited in the format, encoding,
resolution, frame rate. Anything other than the few resolutions, frame rates
etc, are "out of spec".
Here is a chart with the requirments for a DVD:
http://www.mplayerhq.hu/DOCS/HTML/en/menc-feat-vcd-dvd.html

HOWEVER, a modern DVD player will play almost anything, as long as
the internal decoder (hardware or software) will play it. Most computer
programs will too, except earlier versions of Microsoft Media Player for
Windows. It would play files of almost any spec, but if it was playing a
DVD, it would only play ones within spec. I have not tried it in years,
but I expect that limitation is long gone.

I have not seen one in years, but when DVD players first came here (around
1998-1999) the expensive Japanese brand ones were very finicy about the
format of the disk, the zone, how it handled NTSC (24/10001 and 30/10001
frame rates) versus PAL (25) and so on.

Interesting. The player in question was the first commercial DVD player.

The cheap Chinese ones had set up options for TV type (NTSC/PAL/auto)
converting frame rate as needed, and were not very finicy. If it was an
MPEG-1 or MPEG-2 encoded file, it would play it.

Maybe the disk is slightly out of spec in encoding. The only way I know how
to tell is play it with mplayer on a Windows or Linux system and look at
the console output. It will tell you the codec used to decode the video
and audio, the frame rate, the bit rate (how much data is used for encoding),
the resolution etc for both audio and video.

I'll give it a try. Thanks for the suggestion.

 

[William Sommerwerck]

I would try cleaning - and note the 7000 has TWO laser

lenses in a common housing.

One for CDs, I assume.

It's old enough to have picked up a layer of dust in there.
Also worth cleaning that particular disc -- you never know...

I looked at it closely under bright light, and I saw nothing.

I recently had a bad CD which had what appeared to be an area of bad
plating. The replacement did not show this, and played correctly.

I remain amazed at the quality control of optical media. Out of the
thousands of CDs I own, only two have been defective.

 

[Geoffrey S. Mendelson]

I've rented a couple out of maybe two hundred or so bad previously
unplayed DVD movies. I usually run into maybe one bad DVDR in a 100
spindle. Same goes for CD/CDR. These have all been checked in multiple
players/burners.

Back when I first got started in CD recording, late 1991, we paid $10 each
for the blanks (in large quantities) and had a 10% (1 per box of 10)
failure rate.

Office Depot here had a 2 for one sale and I bought 2 100 packs of blanks
on sale and they have been problematic for me, with about a 5% failure rate.
The usual brands I have bought, except for Verbatim, have been closer to 2%
to 3%.

The Verbatim disks I sold here are their special low cost line, and I have had
almost 100% failure rate with them. Compared to the ones sold in the US,
these are absolute junk and a dilution of their brand. I must not be the only
one who thought that because Office Depot had them on half price sale for
around 6 months and no one bought them.

This is not one drive, I currently use 6 computers here with various
drives in them and various operating systems. I do most of my burning on
either a Mac with an external Samsung drive (upgraded from an NEC), and
a Linux computer with an identical drive, but also do it on other computers
with Liteon, LG and NEC drives.

Geoff.