From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) by finch.gentoo.org (Postfix) with ESMTP id 9FCC1138010 for ; Mon, 20 Aug 2012 13:57:15 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id ED87C21C015; Mon, 20 Aug 2012 13:56:21 +0000 (UTC) Received: from svr-us4.tirtonadi.com (svr-us4.tirtonadi.com [69.65.43.212]) by pigeon.gentoo.org (Postfix) with ESMTP id 68635E07C3 for ; Mon, 20 Aug 2012 13:51:15 +0000 (UTC) Received: from mail-vc0-f181.google.com ([209.85.220.181]:41282) by svr-us4.tirtonadi.com with esmtpsa (TLSv1:RC4-SHA:128) (Exim 4.77) (envelope-from ) id 1T3SNx-0013b7-5D for gentoo-user@lists.gentoo.org; Mon, 20 Aug 2012 20:51:17 +0700 Received: by vcbfl17 with SMTP id fl17so5415962vcb.40 for ; Mon, 20 Aug 2012 06:51:14 -0700 (PDT) Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Received: by 10.220.157.65 with SMTP id a1mr10217875vcx.39.1345470673941; Mon, 20 Aug 2012 06:51:13 -0700 (PDT) Received: by 10.220.29.13 with HTTP; Mon, 20 Aug 2012 06:51:13 -0700 (PDT) Received: by 10.220.29.13 with HTTP; Mon, 20 Aug 2012 06:51:13 -0700 (PDT) In-Reply-To: <50322FF3.6050309@alyf.net> References: <20120820102139.GB2928@ca.inter.net> <201208201219.50251.michaelkintzios@gmail.com> <50322FF3.6050309@alyf.net> Date: Mon, 20 Aug 2012 20:51:13 +0700 Message-ID: Subject: Re: [gentoo-user] new machine : DVD drive From: Pandu Poluan To: gentoo-user@lists.gentoo.org Content-Type: multipart/alternative; boundary=f46d043c7eae93742604c7b2cd3a X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - svr-us4.tirtonadi.com X-AntiAbuse: Original Domain - lists.gentoo.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - poluan.info X-Archives-Salt: c2512bc9-3f30-4ed3-9267-170c96ddc867 X-Archives-Hash: 705ee9cb65a6df8ea718ba8c12176805 --f46d043c7eae93742604c7b2cd3a Content-Type: text/plain; charset=UTF-8 On Aug 20, 2012 7:47 PM, "Andrea Conti" wrote: > [snip] > > > > Yes, +RW, -RW, but don't know much more on this other than older DVD writers > > would only do one format not another and if you didn't pay attention to the > > specification/limitations of your hardware you could end up buying the wrong > > type of DVDs. Someone more experienced on recording media could answer this > > better. > > Every modern recorder does both standards; depending on both the burner > and the reader you might find that one standard works better than the > other (i.e. has lower read error rates). Trial and error seems to be the > only working approach... > > As for the standards, if you're just burning backups they're basically > equivalent. The +RW standard is theoretically more flexible as media can > be formatted in a "packet" mode which allows (almost) random r/w access, > but in my experience software support and reliability have always been > lousy, so forget about it. > > +RW media cannot be erased in the same way CD-RWs are erased, -- you can > only overwrite it with new data. -RW behaves the same as CD-RWs in this > regard. > > If you need rewritable DVD media with reliable random r/w access (but > this doesn't seem to be your case), there is a third standard (DVD-RAM) > which uses special disks with hardware sector marks. Drive support is > not hard to find nowadays (the drive you cited actually supports it), > but writing is slow, good media is expensive and the disks cannot be > read in most "normal" dvd drives; I have no idea about the state of > software support in Linux. > +RW *can* be erased, or else it won't be called RW :-) That said, the difference is much deeper than differing metadata. Among which : * +RW uses Phase Modulation, -RW uses amplitude modulation. This gives +RW much more robustness than -RW * +RW blanks provide more info on the energy level required to burn, IIRC up to 4 energy levels each tuned to a certain burning speed (e.g., 1x, 2x, 4x, and 8x). This *greatly* improves the success probability of burning. -RW only provides energy level info for the maximum burning speed; if your drive doesn't support that speed, it'll have to guess, and the results are usually ungood More history : The CD Standard was originally developed by Philips, then adapted to the data world requirements, including CD-R(W). The DVD-R standard was originally developed by Panasonic, but Philips had a spat with Panasonic because in Phillips' view, the CD-R standard has shortcomings they (Philips) want to fix; Panasonic was more interested in getting DVD-R out of the door asap. This resulted in Philips -- together with someone else, was it Sony? -- to independently released the DVD+R standard. CMIIW Rgds, --f46d043c7eae93742604c7b2cd3a Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable


On Aug 20, 2012 7:47 PM, "Andrea Conti" <alyf@alyf.net> wrote:
>

[snip]

> >
> > Yes, +RW, -RW, but don't know much more on this other than ol= der DVD writers
> > would only do one format not another and if you didn't pay at= tention to the
> > specification/limitations of your hardware you could end up buyin= g the wrong
> > type of DVDs. =C2=A0Someone more experienced on recording media c= ould answer this
> > better.
>
> Every modern recorder does both standards; depending on both the burne= r
> and the reader you might find that one standard works better than the<= br> > other (i.e. has lower read error rates). Trial and error seems to be t= he
> only working approach...
>
> As for the standards, if you're just burning backups they're b= asically
> equivalent. The +RW standard is theoretically more flexible as media c= an
> be formatted in a "packet" mode which allows (almost) random= r/w access,
> but in my experience software support and reliability have always been=
> lousy, so forget about it.
>
> +RW media cannot be erased in the same way CD-RWs are erased, -- you c= an
> only overwrite it with new data. -RW behaves the same as CD-RWs in thi= s
> regard.
>
> If you need rewritable DVD media with reliable random r/w access (but<= br> > this doesn't seem to be your case), there is a third standard (DVD= -RAM)
> which uses special disks with hardware sector marks. Drive support is<= br> > not hard to find nowadays (the drive you cited actually supports it),<= br> > but writing is slow, good media is expensive and the disks cannot be > read in most "normal" dvd drives; I have no idea about the s= tate of
> software support in Linux.
>

+RW *can* be erased, or else it won't be called RW :-)

That said, the difference is much deeper than differing metadata. Among = which :

* +RW uses Phase Modulation, -RW uses amplitude modulation. This gives += RW much more robustness than -RW

* +RW blanks provide more info on the energy level required to burn, IIR= C up to 4 energy levels each tuned to a certain burning speed (e.g., 1x, 2x= , 4x, and 8x). This *greatly* improves the success probability of burning. = -RW only provides energy level info for the maximum burning speed; if your = drive doesn't support that speed, it'll have to guess, and the resu= lts are usually ungood

More history :

The CD Standard was originally developed by Philips, then adapted to the= data world requirements, including CD-R(W).=C2=A0 The DVD-R standard was o= riginally developed by Panasonic, but Philips had a spat with Panasonic=C2= =A0 because in Phillips' view, the CD-R standard has shortcomings they = (Philips) want to fix; Panasonic was more interested in getting DVD-R out o= f the door asap. This resulted in Philips -- together with someone else, wa= s it Sony? -- to independently released the DVD+R standard.

CMIIW

Rgds,

--f46d043c7eae93742604c7b2cd3a--