DVD / DVD+R /DVD-R / DVDRW. Are they all really distinct media formats?

"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Rahul" wrote in message
48.16...
I'm always confused by DVD terminology when buying media to write on.
There's DVD / DVD+R / DVD-R / DVDRW and I'm not even sure which more!

Are these all really distinct technologies and formats? Or are some
subsets
/ supersets of others? Or maybe its only backward compatibility issues?
What's the best way to figure out what format my Laptop supports? Do
they
have varied sizes? Does it matter whether I'm writing data or movies
etc.?
I faintly remember there being lead-in / lead-out issues....

I've never faced the problem that I bought some commercial movie etc. on
a
DVD and my Dell Laptop ( Inspirion E1505)'s inbuilt DVD reader /writer
couldn't read it. Its a dual boot so are there any Linux-vs-Win issues
too?

Are these distinctions only relevant when writing disks at home as
opposed
to commercially stamped disks? Or maybe when reading on hardware other
than
"computers" (etc. DVD players etc.)



First: the easy bit. The 'R' media is write once. The 'RW' media can be
erased allowing its re-use.

A little more complex is the difference between the '-' discs and '+'
discs.
As far as you the user is concerned, except for some uses there is little
to
chose. Some older video DVD players will refuse to recognise the DVD+RW
discs (but will recognise DVD+R). This was the result of a deliberate
attempt by Toshiba to discourage the '+' format. Once rumbled they had
to
abandon it.

For DVD-R and DVD+R, there is no practical difference other than the
latter
is written faster by some drives.

For DVD-RW and DVD+RW there is a subtle difference in that the former is
eraseable at the block level only. The latter is eraseable at the word
level. This means that individual words can be erased and overwritten.
It
also means that if used for video, more video can be added to the end of
existing video and the two played through seemlessly. This cannot be
done
with the '-' format.

If you are planning on using packet incemental format (Nero's InCD or
Roxio's Drag-to-disc), then DVD+RW will be much more reliable than
DVD-RW.

Just out of curiosity, why is that? (I don't use the packet writing
format, but am curious, and would have expected the older standard to be
more compatible in this case, too - seems like (from a hardware viewpoint)
it might be "simpler" to just erase the whole block, rather than the
individual word - albeit less desireable for the user).


It is because the read/write head when writing a DVD-RW in the drive, can
only locate positions on the disc to within a block of data. As a result
the drive has to leave a 2 block gap between different data block to avoid
over writing previous data. It is bit hit and miss and consequently it
misses on occasions and overwrites something. If that happens to be part of
the TOC or FAT, then the disc is corrupt and unreadable.

DVD+RW is a bit more technologically advanced such that the read/write head
can locate to a word of data and accurately overwrite it. Thus the
potential for overwriting something important, whilst not entirely removed,
is vastly less likely.

"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Lil' Dave" wrote in message
...
"Rahul" wrote in message
48.16...
"Lil' Dave" wrote in
:


The plus (+) and minus (-) are write formats. Either writer
requirement doesn't really matter. In the end, both can read both
formats if worth their salt.

In the early days, there were DVD players for the TV that could only
read the plus or minus versions. Now, that's not really an issue.
Stamped DVDs is not an issue in any case. For both DVD players and
DVD burners, media quality and reflectivity can determine the outcome
of a readability and burner recognition.

Thanks Dave! I just dug into the specs. for my Dell Inspirion Laptop:
"8X
DVD+/-RW Drive for Inspiron 6400/E1505"

So I guess it can write to both + and - types I assume. They both seem
to
be equally cheap. Any reason to buy one over the other?

--
Rahul


Only if you're burning movies for a + or - specific DVD player for the
TV,
or, one of your share DVD buddies has a picky DVD player on their PC or
TV.

I transcended from the same story of a Technics DVD player that only
reads
+ media.

That is the first time that I have heard of a player that reads the '+'
but
not the '-' format.

Same here. BTW, some older players will not read the DVD+R discs but
will read the DVD-R discs fine. (NB: I'm not talking about the RW discs
here, which you address below)


Then there is something wrong here. The difference relates only to the way
the discs are written. Once a DVD+R is written, there are no different from
a DVD-R (or indeed a premastered DVD). The ID bytes are even the same (in
all 3 cases).

M.I.5¾ wrote:
"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Lil' Dave" wrote in message
...
"Rahul" wrote in message
48.16...
"Lil' Dave" wrote in
:


The plus (+) and minus (-) are write formats. Either writer
requirement doesn't really matter. In the end, both can read both
formats if worth their salt.

In the early days, there were DVD players for the TV that could only
read the plus or minus versions. Now, that's not really an issue.
Stamped DVDs is not an issue in any case. For both DVD players and
DVD burners, media quality and reflectivity can determine the outcome
of a readability and burner recognition.

Thanks Dave! I just dug into the specs. for my Dell Inspirion Laptop:
"8X DVD+/-RW Drive for Inspiron 6400/E1505"

So I guess it can write to both + and - types I assume. They both seem
to be equally cheap. Any reason to buy one over the other?

--
Rahul


Only if you're burning movies for a + or - specific DVD player for the
TV,
or, one of your share DVD buddies has a picky DVD player on their PC or
TV.

I transcended from the same story of a Technics DVD player that only
reads + media.

That is the first time that I have heard of a player that reads the '+'
but not the '-' format.

Same here. BTW, some older players will not read the DVD+R discs but
will read the DVD-R discs fine. (NB: I'm not talking about the RW
discs
here, which you address below)


Then there is something wrong here. The difference relates only to the
way
the discs are written. Once a DVD+R is written, there are no different
from
a DVD-R (or indeed a premastered DVD). The ID bytes are even the same (in
all 3 cases).

Evidently there is SOME difference. We know the DVD+R discs are
manufactured at least in some way different from the DVD-R discs, but
whether the problem is with reading the disc themselves, or the way it is
written to the disc, I can't say. But one thing I can say: I have on at
least a couple of occasions had discs I made using DVD+Rs that could not be
read by my older DVD players, whereas when I made them using DVD-R discs,
they worked perfectly. And yes, the DVD writer was able to write both
types of discs.

There was also some article covering this very point that I read some time
ago on the net, so it's not like it was just my case alone. The
recommendation then was to use the DVD-Rs for better backward compatibility,
and from what little I have seen, they were correct.

M.I.5¾ wrote:
"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Rahul" wrote in message
48.16...
I'm always confused by DVD terminology when buying media to write on.
There's DVD / DVD+R / DVD-R / DVDRW and I'm not even sure which more!

Are these all really distinct technologies and formats? Or are some
subsets
/ supersets of others? Or maybe its only backward compatibility issues?
What's the best way to figure out what format my Laptop supports? Do
they have varied sizes? Does it matter whether I'm writing data or
movies
etc.? I faintly remember there being lead-in / lead-out issues....

I've never faced the problem that I bought some commercial movie etc.
on
a DVD and my Dell Laptop ( Inspirion E1505)'s inbuilt DVD reader
/writer
couldn't read it. Its a dual boot so are there any Linux-vs-Win issues
too?

Are these distinctions only relevant when writing disks at home as
opposed
to commercially stamped disks? Or maybe when reading on hardware other
than "computers" (etc. DVD players etc.)

First: the easy bit. The 'R' media is write once. The 'RW' media can
be
erased allowing its re-use.

A little more complex is the difference between the '-' discs and '+'
discs.
As far as you the user is concerned, except for some uses there is
little to
chose. Some older video DVD players will refuse to recognise the DVD+RW
discs (but will recognise DVD+R). This was the result of a deliberate
attempt by Toshiba to discourage the '+' format. Once rumbled they had
to abandon it.

For DVD-R and DVD+R, there is no practical difference other than the
latter is written faster by some drives.

AND that the DVD-R discs are more compatible with some older players.
(BTDT)

I've already covered this point. There should be no difference. I am
not
aware of any player that will not play DVD+R discs (even first generation
players play them flawlessly) unless the player's laser has deteriorated -
but then they won't play lots of formats.

Well, that's not the only reason. Come over and see for yourself. :-)

It was the DVD+RW that gave all
the problems but only because players were deliberately rigged to refuse
to
play them.

Well, as I said in my other post, evidently there is some difference. To
recap:

We know the DVD+R discs are manufactured at least in some way different from
the DVD-R discs, but whether the problem is with reading the disc
themselves, or the way it is written to the disc, I can't say. But one
thing I can say: I have on at least a couple of occasions had discs I made
using DVD+Rs that could not be read by my older DVD players, whereas when I
made them using DVD-R discs, they worked perfectly. And yes, the DVD
writer was able to write both types of discs.

There was also some article covering this very point that I read some time
ago on the net, so it's not like it was just my case alone. The
recommendation then was to use the DVD-Rs for better backward compatibility,
and from what little I have seen, they were correct.


For DVD-RW and DVD+RW there is a subtle difference in that the former is
eraseable at the block level only. The latter is eraseable at the word
level. This means that individual words can be erased and overwritten.
It also means that if used for video, more video can be added to the end
of
existing video and the two played through seemlessly. This cannot be
done with the '-' format.

If you are planning on using packet incemental format (Nero's InCD or
Roxio's Drag-to-disc), then DVD+RW will be much more reliable than
DVD-RW.

Does any truly sane person use the packet writing stuff? Too many
potential problems there. :-) InCD and DirectCD, thanks, but no
thanks.


Whilst I agree with you, many people do. DVD+RW discs give few problems
with packet writing unlike DVD-RW and CD-RW. But if your drive supports
DVD-RAM use that instead.

I'd rather just stick with the tried and true DVD-R discs, which work on
about anything.

And another side benefit is that there are NO problematic conflicts between
(or even due to any) packet writing stuff. I have BOTH Nero *and* EZCD
installed on my computer, but sanely WITHOUT any InCD and DirectCD crap
being installed.

As in, "thanks, but no thanks".

M.I.5¾ wrote:
"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Rahul" wrote in message
48.16...
I'm always confused by DVD terminology when buying media to write on.
There's DVD / DVD+R / DVD-R / DVDRW and I'm not even sure which more!

Are these all really distinct technologies and formats? Or are some
subsets
/ supersets of others? Or maybe its only backward compatibility issues?
What's the best way to figure out what format my Laptop supports? Do
they
have varied sizes? Does it matter whether I'm writing data or movies
etc.?
I faintly remember there being lead-in / lead-out issues....

I've never faced the problem that I bought some commercial movie etc.
on
a
DVD and my Dell Laptop ( Inspirion E1505)'s inbuilt DVD reader /writer
couldn't read it. Its a dual boot so are there any Linux-vs-Win issues
too?

Are these distinctions only relevant when writing disks at home as
opposed
to commercially stamped disks? Or maybe when reading on hardware other
than
"computers" (etc. DVD players etc.)



First: the easy bit. The 'R' media is write once. The 'RW' media can
be
erased allowing its re-use.

A little more complex is the difference between the '-' discs and '+'
discs.
As far as you the user is concerned, except for some uses there is
little
to
chose. Some older video DVD players will refuse to recognise the DVD+RW
discs (but will recognise DVD+R). This was the result of a deliberate
attempt by Toshiba to discourage the '+' format. Once rumbled they had
to
abandon it.

For DVD-R and DVD+R, there is no practical difference other than the
latter
is written faster by some drives.

For DVD-RW and DVD+RW there is a subtle difference in that the former is
eraseable at the block level only. The latter is eraseable at the word
level. This means that individual words can be erased and overwritten.
It
also means that if used for video, more video can be added to the end of
existing video and the two played through seemlessly. This cannot be
done
with the '-' format.

If you are planning on using packet incemental format (Nero's InCD or
Roxio's Drag-to-disc), then DVD+RW will be much more reliable than
DVD-RW.

Just out of curiosity, why is that? (I don't use the packet writing
format, but am curious, and would have expected the older standard to be
more compatible in this case, too - seems like (from a hardware
viewpoint)
it might be "simpler" to just erase the whole block, rather than the
individual word - albeit less desireable for the user).


It is because the read/write head when writing a DVD-RW in the drive, can
only locate positions on the disc to within a block of data. As a result
the drive has to leave a 2 block gap between different data block to avoid
over writing previous data. It is bit hit and miss and consequently it
misses on occasions and overwrites something. If that happens to be part
of
the TOC or FAT, then the disc is corrupt and unreadable.

DVD+RW is a bit more technologically advanced such that the read/write
head
can locate to a word of data and accurately overwrite it. Thus the
potential for overwriting something important, whilst not entirely
removed,
is vastly less likely.

Interesting. So if this is really true, then I expect the DVD+RW has
replaced the DVD-RWs in the stores by now, but I never use them, so I don't
know.

"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Rahul" wrote in message
48.16...
I'm always confused by DVD terminology when buying media to write on.
There's DVD / DVD+R / DVD-R / DVDRW and I'm not even sure which more!

Are these all really distinct technologies and formats? Or are some
subsets
/ supersets of others? Or maybe its only backward compatibility
issues?
What's the best way to figure out what format my Laptop supports? Do
they have varied sizes? Does it matter whether I'm writing data or
movies
etc.? I faintly remember there being lead-in / lead-out issues....

I've never faced the problem that I bought some commercial movie etc.
on
a DVD and my Dell Laptop ( Inspirion E1505)'s inbuilt DVD reader
/writer
couldn't read it. Its a dual boot so are there any Linux-vs-Win
issues too?

Are these distinctions only relevant when writing disks at home as
opposed
to commercially stamped disks? Or maybe when reading on hardware other
than "computers" (etc. DVD players etc.)

First: the easy bit. The 'R' media is write once. The 'RW' media can
be
erased allowing its re-use.

A little more complex is the difference between the '-' discs and '+'
discs.
As far as you the user is concerned, except for some uses there is
little to
chose. Some older video DVD players will refuse to recognise the
DVD+RW
discs (but will recognise DVD+R). This was the result of a deliberate
attempt by Toshiba to discourage the '+' format. Once rumbled they had
to abandon it.

For DVD-R and DVD+R, there is no practical difference other than the
latter is written faster by some drives.

AND that the DVD-R discs are more compatible with some older players.
(BTDT)

I've already covered this point. There should be no difference. I am
not
aware of any player that will not play DVD+R discs (even first generation
players play them flawlessly) unless the player's laser has
deteriorated -
but then they won't play lots of formats.

Well, that's not the only reason. Come over and see for yourself. :-)

It was the DVD+RW that gave all
the problems but only because players were deliberately rigged to refuse
to
play them.

Well, as I said in my other post, evidently there is some difference. To
recap:

We know the DVD+R discs are manufactured at least in some way different
from the DVD-R discs, but whether the problem is with reading the disc
themselves, or the way it is written to the disc, I can't say. But one
thing I can say: I have on at least a couple of occasions had discs I
made using DVD+Rs that could not be read by my older DVD players, whereas
when I made them using DVD-R discs, they worked perfectly. And yes, the
DVD writer was able to write both types of discs.


As I said before, the difference in the technology relates purely in the way
the disc is written. It is related to providing the write laser the ability
to accurately position burns subsequent to the first burn. Once the disc is
written, as far as reading the disc is concerned there is absolutely no
difference between them.

There was also some article covering this very point that I read some time
ago on the net, so it's not like it was just my case alone. The
recommendation then was to use the DVD-Rs for better backward
compatibility, and from what little I have seen, they were correct.


Again as I said before, this recommendation arose because quite a number of
video DVD players wouldn't read DVD+RW discs (the DVD+R didn't exist at this
point). Thus the story quickly spread that the '+' format wasn't fully
compatible with all DVD players. It was only when the DVD+R discs appeared
that it was discovered that the players that wouldn't play DVD+RW discs,
quite flawlessly played the DVD+R discs. This totally went against the
claimed reasons for the incompatibility. On investigation, it was found
that some video DVD players were reading the compatibility ID byte off the
disc (something that video players had no reason to do). If the ID byte was
'0' (DVD_ROM, DVD-R or DVD+R) or '1' (DVD-RW) then the player would play the
disc, but if the ID byte was '2' (indicating a DVD+RW disc - or more
accurately, indicating that the disc was byte eraseable and writable) the
player then executed a software routine that made the laser and motor behave
as though a non readable disc had been inserted, finally giving an error
message about incompatible format.

It was quickly realised that it was Toshiba players that did this and less
quickly realised that any other badged players where the player mechanism
was made by Toshiba. It should be remembered that it was Toshiba that
resisted the introduction of the '+' format, and Toshiba who was behind the
refusal to allow the '+' format to use the standard DVD logo on drives and
discs. Once Toshiba had succeeded in excluding the '+' format, it became
obvious that the DVD consortium would receive no revenue from this 'rogue'
format and so Toshiba had a vested interest in ensuring its demise. Once
the culprit was identified, the news travelled with Internet speed around
the planet and Toshiba suddenly found itself facing a consumer boycott*.
Toshiba had to a bit of backpedalling, and now their video players will play
DVD+RW format discs, but the their video DVD recorders continue not to
support the format, though to be fair to Toshiba the DVD+VR video recorder
format for DVD+RW is very different to the DVD-VR format for DVD-RW and
somewhat less flexible.

* In fact the Richer Sounds chain actually stopped stocking their goods
because no one would buy them.


For DVD-RW and DVD+RW there is a subtle difference in that the former
is
eraseable at the block level only. The latter is eraseable at the word
level. This means that individual words can be erased and overwritten.
It also means that if used for video, more video can be added to the
end of
existing video and the two played through seemlessly. This cannot be
done with the '-' format.

If you are planning on using packet incemental format (Nero's InCD or
Roxio's Drag-to-disc), then DVD+RW will be much more reliable than
DVD-RW.

Does any truly sane person use the packet writing stuff? Too many
potential problems there. :-) InCD and DirectCD, thanks, but no
thanks.


Whilst I agree with you, many people do. DVD+RW discs give few problems
with packet writing unlike DVD-RW and CD-RW. But if your drive supports
DVD-RAM use that instead.

I'd rather just stick with the tried and true DVD-R discs, which work on
about anything.


Virtually all my video DVD discs have been produced in DVD+R format and I've
never had a complaint. The only time I use DVD-R is for material that is
recorded on my DVD recorder. But even here, I will often record to DVD-RAM
and then transfer to DVD+R using authoring software if necessary. This also
allows me to add the widescreen flags which few, if any, video recorders
support when producing standard format video discs.

All of my data discs are DVD+R or DVD+RW.

"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Rahul" wrote in message
48.16...
I'm always confused by DVD terminology when buying media to write on.
There's DVD / DVD+R / DVD-R / DVDRW and I'm not even sure which more!

Are these all really distinct technologies and formats? Or are some
subsets
/ supersets of others? Or maybe its only backward compatibility
issues?
What's the best way to figure out what format my Laptop supports? Do
they
have varied sizes? Does it matter whether I'm writing data or movies
etc.?
I faintly remember there being lead-in / lead-out issues....

I've never faced the problem that I bought some commercial movie etc.
on
a
DVD and my Dell Laptop ( Inspirion E1505)'s inbuilt DVD reader /writer
couldn't read it. Its a dual boot so are there any Linux-vs-Win
issues
too?

Are these distinctions only relevant when writing disks at home as
opposed
to commercially stamped disks? Or maybe when reading on hardware other
than
"computers" (etc. DVD players etc.)



First: the easy bit. The 'R' media is write once. The 'RW' media can
be
erased allowing its re-use.

A little more complex is the difference between the '-' discs and '+'
discs.
As far as you the user is concerned, except for some uses there is
little
to
chose. Some older video DVD players will refuse to recognise the
DVD+RW
discs (but will recognise DVD+R). This was the result of a deliberate
attempt by Toshiba to discourage the '+' format. Once rumbled they had
to
abandon it.

For DVD-R and DVD+R, there is no practical difference other than the
latter
is written faster by some drives.

For DVD-RW and DVD+RW there is a subtle difference in that the former
is
eraseable at the block level only. The latter is eraseable at the word
level. This means that individual words can be erased and overwritten.
It
also means that if used for video, more video can be added to the end
of
existing video and the two played through seemlessly. This cannot be
done
with the '-' format.

If you are planning on using packet incemental format (Nero's InCD or
Roxio's Drag-to-disc), then DVD+RW will be much more reliable than
DVD-RW.

Just out of curiosity, why is that? (I don't use the packet writing
format, but am curious, and would have expected the older standard to be
more compatible in this case, too - seems like (from a hardware
viewpoint)
it might be "simpler" to just erase the whole block, rather than the
individual word - albeit less desireable for the user).


It is because the read/write head when writing a DVD-RW in the drive, can
only locate positions on the disc to within a block of data. As a result
the drive has to leave a 2 block gap between different data block to
avoid
over writing previous data. It is bit hit and miss and consequently it
misses on occasions and overwrites something. If that happens to be part
of
the TOC or FAT, then the disc is corrupt and unreadable.

DVD+RW is a bit more technologically advanced such that the read/write
head
can locate to a word of data and accurately overwrite it. Thus the
potential for overwriting something important, whilst not entirely
removed,
is vastly less likely.

Interesting. So if this is really true, then I expect the DVD+RW has
replaced the DVD-RWs in the stores by now, but I never use them, so I
don't know.

Well, in theory it might have done, but there are two reasons (at least) why
it hasn't. First, most users are unaware of the differences behind the
technology. Most regard it as a VHS/Betamax thing, which it isn't really
because each's drive can generally play the other (not the case for VHS and
Betamax). Second, the rule of thumb that you should record video to '-'
discs and 'data to '+' discs still abounds*. Many people will give you this
advice, but they often don't actually know why (Shop assistants in
particular are good at this). It is something that someone has told them
and they repeat it authoritatively.

* At least one disc manufacturer marks the '-' discs 'for Video recording'
and the '+' discs 'for Data recording'.

M.I.5¾ wrote:
"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Rahul" wrote in message
snip

First: the easy bit. The 'R' media is write once. The 'RW' media can
be erased allowing its re-use.

A little more complex is the difference between the '-' discs and '+'
discs.
As far as you the user is concerned, except for some uses there is
little to
chose. Some older video DVD players will refuse to recognise the
DVD+RW
discs (but will recognise DVD+R). This was the result of a deliberate
attempt by Toshiba to discourage the '+' format. Once rumbled they
had
to abandon it.

For DVD-R and DVD+R, there is no practical difference other than the
latter is written faster by some drives.

AND that the DVD-R discs are more compatible with some older players.
(BTDT)

I've already covered this point. There should be no difference.

Maybe there "shouldn't be", but there is.

I am not aware of any player that will not play DVD+R discs

I am. (One or two of the older ones I still have).

(even first generation players play them flawlessly) unless the player's
laser
has deteriorated - but then they won't play lots of formats.

Well, that's not the only reason. Come over and see for yourself.
:-)

It was the DVD+RW that gave all
the problems but only because players were deliberately rigged to refuse
to play them.

Well, as I said in my other post, evidently there is some difference.
To
recap:

We know the DVD+R discs are manufactured at least in some way different
from the DVD-R discs, but whether the problem is with reading the disc
themselves, or the way it is written to the disc, I can't say. But one
thing I can say: I have on at least a couple of occasions had discs I
made using DVD+Rs that could not be read by my older DVD players, whereas
when I made them using DVD-R discs, they worked perfectly. And yes, the
DVD writer was able to write both types of discs.

As I said before, the difference in the technology relates purely in the
way
the disc is written. It is related to providing the write laser the
ability
to accurately position burns subsequent to the first burn. Once the disc
is
written, as far as reading the disc is concerned there is absolutely no
difference between them.

Then why can't my older DVD player read mine? (I mean when I tried outa few
DVD+R discs that I made, but worked perfectly fine when I used the DVD-R
discs)? The DVD writer was compatible for both formats.

Anyways, that's what happened. (Again, I'm NOT talking about RW discs
which I have never used, nor intend to). Perhaps it is possible that my
DVD writer can't write the +Rs as well as the -Rs, but I seriously doubt it,
since it's spec'd for both.

There was also some article covering this very point that I read some
time
ago on the net, so it's not like it was just my case alone. The
recommendation then was to use the DVD-Rs for better backward
compatibility, and from what little I have seen, they were correct.

Again as I said before, this recommendation arose because quite a number
of
video DVD players wouldn't read DVD+RW discs (the DVD+R didn't exist at
this
point).

(But it certainly did at the point for the article I'm talking about. More
below).

Thus the story quickly spread that the '+' format wasn't fully
compatible with all DVD players.

And actually, it isn't. Again, I have witnessed that first hand over here,
as I've repeatedly stated. (I'm not talking about the players on the
computer, I'm talking about some older home audio DVD player). But I do
find it interesting that you have never had a compatibility problem with the
DVD+Rs, however.

snip

"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Rahul" wrote in message
snip

First: the easy bit. The 'R' media is write once. The 'RW' media
can
be erased allowing its re-use.

A little more complex is the difference between the '-' discs and '+'
discs.
As far as you the user is concerned, except for some uses there is
little to
chose. Some older video DVD players will refuse to recognise the
DVD+RW
discs (but will recognise DVD+R). This was the result of a
deliberate
attempt by Toshiba to discourage the '+' format. Once rumbled they
had
to abandon it.

For DVD-R and DVD+R, there is no practical difference other than the
latter is written faster by some drives.

AND that the DVD-R discs are more compatible with some older players.
(BTDT)

I've already covered this point. There should be no difference.

Maybe there "shouldn't be", but there is.

I am not aware of any player that will not play DVD+R discs

I am. (One or two of the older ones I still have).


Why don't you identify these mystery machines?

(even first generation players play them flawlessly) unless the
player's laser
has deteriorated - but then they won't play lots of formats.

Well, that's not the only reason. Come over and see for yourself. :-)

It was the DVD+RW that gave all
the problems but only because players were deliberately rigged to
refuse
to play them.

Well, as I said in my other post, evidently there is some difference. To
recap:

We know the DVD+R discs are manufactured at least in some way different
from the DVD-R discs, but whether the problem is with reading the disc
themselves, or the way it is written to the disc, I can't say. But one
thing I can say: I have on at least a couple of occasions had discs I
made using DVD+Rs that could not be read by my older DVD players,
whereas
when I made them using DVD-R discs, they worked perfectly. And yes,
the
DVD writer was able to write both types of discs.

As I said before, the difference in the technology relates purely in the
way
the disc is written. It is related to providing the write laser the
ability
to accurately position burns subsequent to the first burn. Once the disc
is
written, as far as reading the disc is concerned there is absolutely no
difference between them.

Then why can't my older DVD player read mine? (I mean when I tried outa
few DVD+R discs that I made, but worked perfectly fine when I used the
DVD-R discs)? The DVD writer was compatible for both formats.

Anyways, that's what happened. (Again, I'm NOT talking about RW discs
which I have never used, nor intend to). Perhaps it is possible that my
DVD writer can't write the +Rs as well as the -Rs, but I seriously doubt
it, since it's spec'd for both.

There was also some article covering this very point that I read some
time
ago on the net, so it's not like it was just my case alone. The
recommendation then was to use the DVD-Rs for better backward
compatibility, and from what little I have seen, they were correct.

Again as I said before, this recommendation arose because quite a number
of
video DVD players wouldn't read DVD+RW discs (the DVD+R didn't exist at
this
point).

(But it certainly did at the point for the article I'm talking about.
More below).

Thus the story quickly spread that the '+' format wasn't fully
compatible with all DVD players.

And actually, it isn't. Again, I have witnessed that first hand over
here, as I've repeatedly stated. (I'm not talking about the players on
the computer, I'm talking about some older home audio DVD player). But
I do find it interesting that you have never had a compatibility problem
with the DVD+Rs, however.


Name the player and I will look it up.

M.I.5¾ wrote:
"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Rahul" wrote in message
snip

First: the easy bit. The 'R' media is write once. The 'RW' media
can be erased allowing its re-use.

A little more complex is the difference between the '-' discs and
'+'
discs.
As far as you the user is concerned, except for some uses there is
little to
chose. Some older video DVD players will refuse to recognise the
DVD+RW
discs (but will recognise DVD+R). This was the result of a
deliberate
attempt by Toshiba to discourage the '+' format. Once rumbled they
had to abandon it.

For DVD-R and DVD+R, there is no practical difference other than the
latter is written faster by some drives.

AND that the DVD-R discs are more compatible with some older players.
(BTDT)

I've already covered this point. There should be no difference.

Maybe there "shouldn't be", but there is.

I am not aware of any player that will not play DVD+R discs

I am. (One or two of the older ones I still have).

Why don't you identify these mystery machines?

Well, one that comes to mind is my JVC HR-XVC1U unit. (It's an older
DVD (and CD) and VHS combo player deck)

(even first generation players play them flawlessly) unless the
player's laser has deteriorated - but then they won't play lots of
formats.

Well, that's not the only reason. Come over and see for yourself.
:-)

It was the DVD+RW that gave all
the problems but only because players were deliberately rigged to
refuse to play them.

Well, as I said in my other post, evidently there is some difference.
To
recap:

We know the DVD+R discs are manufactured at least in some way different
from the DVD-R discs, but whether the problem is with reading the disc
themselves, or the way it is written to the disc, I can't say. But
one
thing I can say: I have on at least a couple of occasions had discs I
made using DVD+Rs that could not be read by my older DVD players,
whereas
when I made them using DVD-R discs, they worked perfectly. And yes,
the DVD writer was able to write both types of discs.

As I said before, the difference in the technology relates purely in the
way
the disc is written. It is related to providing the write laser the
ability
to accurately position burns subsequent to the first burn. Once the
disc
is written, as far as reading the disc is concerned there is absolutely
no
difference between them.

Then why can't my older DVD player read mine? (I mean when I tried outa
few DVD+R discs that I made, but worked perfectly fine when I used the
DVD-R discs)? The DVD writer was compatible for both formats.

Anyways, that's what happened. (Again, I'm NOT talking about RW discs
which I have never used, nor intend to). Perhaps it is possible that my
DVD writer can't write the +Rs as well as the -Rs, but I seriously doubt
it, since it's spec'd for both.

There was also some article covering this very point that I read some
time ago on the net, so it's not like it was just my case alone. The
recommendation then was to use the DVD-Rs for better backward
compatibility, and from what little I have seen, they were correct.

Again as I said before, this recommendation arose because quite a number
of
video DVD players wouldn't read DVD+RW discs (the DVD+R didn't exist at
this point).

(But it certainly did at the point for the article I'm talking about.
More below).

Thus the story quickly spread that the '+' format wasn't fully
compatible with all DVD players.

And actually, it isn't. Again, I have witnessed that first hand over
here, as I've repeatedly stated. (I'm not talking about the players on
the computer, I'm talking about some older home audio DVD player). But
I do find it interesting that you have never had a compatibility problem
with the DVD+Rs, however.


Name the player and I will look it up.

JVC HR-XVC1U (mentioned above)

"Bill in Co." wrote in message
...
M.I.5¾ wrote:

Name the player and I will look it up.

JVC HR-XVC1U (mentioned above)


Comes up as:

Compatible with DVD-R

Compatible with DVD-RW

Partially compatible with DVD-R9 (Plays layer 0 only)

Compatible with DVD+R.

Not compatible with DVD+RW.

Not compatible with DVD+R9.

No information on RW9 discs but unlikely to be compatible.

The DVD mechanism of this machine is made by Toshiba. Apparently it is a
DVD/VHS combo unit and the VHS mechanism is made by JVC themselves.

DVD+RW discs can be made to play by changing the Compatibility ID byte from
'2' to '0' - there are numerous utilities that do this. It is necessary to
change it back before erasing and reusing the disc.

It is possible that the particular brand of blank DVD+R discs that you used
may not have had a good image made when recorded in your burner. You could
try burning it at a lower speed (this often works). Alternatively, try a
different brand - they are not all as equal as they should be.

M.I.5¾ wrote:
"Bill in Co." wrote in message
...
M.I.5¾ wrote:

Name the player and I will look it up.

JVC HR-XVC1U (mentioned above)

Comes up as:

Compatible with DVD-R

Compatible with DVD-RW

Partially compatible with DVD-R9 (Plays layer 0 only)

Compatible with DVD+R.

Allegedly, anyways. More below.

Not compatible with DVD+RW.

Not compatible with DVD+R9.

No information on RW9 discs but unlikely to be compatible.

The DVD mechanism of this machine is made by Toshiba. Apparently it is a
DVD/VHS combo unit and the VHS mechanism is made by JVC themselves.

Interesting.

DVD+RW discs can be made to play by changing the Compatibility ID byte
from
'2' to '0' - there are numerous utilities that do this. It is necessary
to
change it back before erasing and reusing the disc.

It is possible that the particular brand of blank DVD+R discs that you
used
may not have had a good image made when recorded in your burner.

It happened on more than one occasion. In fact, none of the few DVD+R's
that I tried ever worked on my deck. But more on that below.

You could
try burning it at a lower speed (this often works). Alternatively, try a
different brand - they are not all as equal as they should be.

When I did the experiments, I'm pretty sure I was using the same brand of
DVD discs for both (Memorex, IIRC).

I didn't try using a slower than "normal" speed, but then again, the speed
was pretty slow, anyways, since my DVD/CD burner was a bit older (Memorex
True 8X, and rated at that for both +R and -R formats). But the Memorex
DVD discs were also rated at 8X (this was some time ago, when that was
common).

But thanks for the info and looking it up.

On Fri, 11 Jul 2008 10:16:07 +0100, "M.I.5¾"
wrote:


"Bill in Co." wrote in message
...
M.I.5¾ wrote:

Name the player and I will look it up.

JVC HR-XVC1U (mentioned above)


Comes up as:

Compatible with DVD-R

Compatible with DVD-RW

Partially compatible with DVD-R9 (Plays layer 0 only)

Compatible with DVD+R.

Not compatible with DVD+RW.

Not compatible with DVD+R9.

No information on RW9 discs but unlikely to be compatible.

The DVD mechanism of this machine is made by Toshiba. Apparently it is a
DVD/VHS combo unit and the VHS mechanism is made by JVC themselves.

DVD+RW discs can be made to play by changing the Compatibility ID byte from
'2' to '0' - there are numerous utilities that do this. It is necessary to
change it back before erasing and reusing the disc.

It is possible that the particular brand of blank DVD+R discs that you used
may not have had a good image made when recorded in your burner. You could
try burning it at a lower speed (this often works). Alternatively, try a
different brand - they are not all as equal as they should be.





So has spoken they hypocrite

If I can jump in that mention of -RW not reading as precisely as +RW: My
Samsung R100 seems to be wearing out after three years, early on used with
lots of dusty disks: it rejects many once-used disks (-RW) as unreadable.
This is progressing, from rarely to occasionally (randomly) to now where
anything but a fresh disk is unreadable. I assume the hardware mechanism
that positions the read-write head gets confused/lost as it navigates the
disk: it wobbles too much or diffracts the signal too much to read it
accurately.

"M.I.5¾" wrote:


"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Rahul" wrote in message
48.16...
I'm always confused by DVD terminology when buying media to write on.
There's DVD / DVD+R / DVD-R / DVDRW and I'm not even sure which more!

Are these all really distinct technologies and formats? Or are some
subsets
/ supersets of others? Or maybe its only backward compatibility issues?
What's the best way to figure out what format my Laptop supports? Do
they
have varied sizes? Does it matter whether I'm writing data or movies
etc.?
I faintly remember there being lead-in / lead-out issues....

I've never faced the problem that I bought some commercial movie etc. on
a
DVD and my Dell Laptop ( Inspirion E1505)'s inbuilt DVD reader /writer
couldn't read it. Its a dual boot so are there any Linux-vs-Win issues
too?

Are these distinctions only relevant when writing disks at home as
opposed
to commercially stamped disks? Or maybe when reading on hardware other
than
"computers" (etc. DVD players etc.)



First: the easy bit. The 'R' media is write once. The 'RW' media can be
erased allowing its re-use.

A little more complex is the difference between the '-' discs and '+'
discs.
As far as you the user is concerned, except for some uses there is little
to
chose. Some older video DVD players will refuse to recognise the DVD+RW
discs (but will recognise DVD+R). This was the result of a deliberate
attempt by Toshiba to discourage the '+' format. Once rumbled they had
to
abandon it.

For DVD-R and DVD+R, there is no practical difference other than the
latter
is written faster by some drives.

For DVD-RW and DVD+RW there is a subtle difference in that the former is
eraseable at the block level only. The latter is eraseable at the word
level. This means that individual words can be erased and overwritten.
It
also means that if used for video, more video can be added to the end of
existing video and the two played through seemlessly. This cannot be
done
with the '-' format.

If you are planning on using packet incemental format (Nero's InCD or
Roxio's Drag-to-disc), then DVD+RW will be much more reliable than
DVD-RW.

Just out of curiosity, why is that? (I don't use the packet writing
format, but am curious, and would have expected the older standard to be
more compatible in this case, too - seems like (from a hardware viewpoint)
it might be "simpler" to just erase the whole block, rather than the
individual word - albeit less desireable for the user).


It is because the read/write head when writing a DVD-RW in the drive, can
only locate positions on the disc to within a block of data. As a result
the drive has to leave a 2 block gap between different data block to avoid
over writing previous data. It is bit hit and miss and consequently it
misses on occasions and overwrites something. If that happens to be part of
the TOC or FAT, then the disc is corrupt and unreadable.

DVD+RW is a bit more technologically advanced such that the read/write head
can locate to a word of data and accurately overwrite it. Thus the
potential for overwriting something important, whilst not entirely removed,
is vastly less likely.

"Bill in Co." wrote in message
...
M.I.5¾ wrote:
"Bill in Co." wrote in message
...
M.I.5¾ wrote:

Name the player and I will look it up.

JVC HR-XVC1U (mentioned above)

Comes up as:

Compatible with DVD-R

Compatible with DVD-RW

Partially compatible with DVD-R9 (Plays layer 0 only)

Compatible with DVD+R.

Allegedly, anyways. More below.

Not compatible with DVD+RW.

Not compatible with DVD+R9.

No information on RW9 discs but unlikely to be compatible.

The DVD mechanism of this machine is made by Toshiba. Apparently it is a
DVD/VHS combo unit and the VHS mechanism is made by JVC themselves.

Interesting.

DVD+RW discs can be made to play by changing the Compatibility ID byte
from
'2' to '0' - there are numerous utilities that do this. It is necessary
to
change it back before erasing and reusing the disc.

It is possible that the particular brand of blank DVD+R discs that you
used
may not have had a good image made when recorded in your burner.

It happened on more than one occasion. In fact, none of the few
DVD+R's that I tried ever worked on my deck. But more on that below.

You could
try burning it at a lower speed (this often works). Alternatively, try a
different brand - they are not all as equal as they should be.

When I did the experiments, I'm pretty sure I was using the same brand of
DVD discs for both (Memorex, IIRC).

I didn't try using a slower than "normal" speed, but then again, the speed
was pretty slow, anyways, since my DVD/CD burner was a bit older (Memorex
True 8X, and rated at that for both +R and -R formats). But the Memorex
DVD discs were also rated at 8X (this was some time ago, when that was
common).

But thanks for the info and looking it up.

There are no issues with Memorex blanks that I am aware of.

It might be worth your while trying a burn at 2.4x.