Difference between DVD-R and DVD+R

jovejupiter · Joined: Dec 12, 2004 Posts: 133

I recently needed to send a couple of DVDs with video clips to a colleague in the USA. Both discs had identical contents - a short NTSC MPG2 clip with a simple menu. The total file size was 105MB.

Some video players seem to prefer either DVD+R or DVD-R, so I recorded the files on both formats.

Both discs played OK on my multi format system and both discs showed the same file sizes in Windows Explorer, but the recorded band on the DVD+R disc was about 8mm wide, whilst the recorded band on the DVD-R disc was about 13mm wide.

Both discs are listed as storing 4.7GB.

I'm curious as to why there is a difference.

Can anybody enlighten me.

TIA

Tony

drwho07 · Joined: Nov 29, 2007 Posts: 1546 Location: Central FL, USA

So I've been told, there is extra data on the DVD-R disks.
That would account for the extra width of the data area.

I had so many problems with the -R disks, in the past, that I just won't use them.

Many of the stores around here are selling the -R dvd's at a lower price than the +R disks..... I can only assume it's because most people won't buy them. I won't!

It's amazing what you can find with a simple Google search. I found this:

Competing formats
A single DVD-R disc
A DVD-R jewel case
A spindle with 50 Verbatim DVD-R discs

A previous DVD recordable format called DVD-RAM (DVD random access memory) predates DVD-R. Developed in 1996, DVD-RAM is a rewritable optical disc usually encased in a cartridge. Currently available in standard 4.7 GB (4.377 GiB), it is ideal for use that requires quick revisions and rewriting. In 2002 a new format was developed called DVD+R (or "plus" R). Created by a coalition called the DVD+RW Alliance, this format uses a number of improved technologies that, while generally unnoticeable to the end user, make a more reliable technology. One example is the ADIP (ADdress In Pregroove) system of tracking and speed control used by DVD+R being less susceptible to interference and error than the LPP (Land Pre Pit) system used by DVD-R, which makes the ADIP system more accurate at higher speeds. In addition, DVD+R(W) has a more robust error management system than DVD-R(W), allowing for more accurate burning to media independent of the quality of the media. Additional session linking methods are more accurate with DVD+R(W) versus DVD-R(W), resulting in fewer damaged or unusable discs due to buffer under-run and multi-session disks with fewer PI/PO errors.[2]

This new format, among other things, resulted in DVD-R being unofficially referred to as DVD "minus" R (though in countries where British English is dominant, the term "minus R" was already common; not just in contrast to "plus R")[3][4]. DVD-R and DVD+R technologies are not directly compatible, which created a format war in the DVD technology industry. To reconcile the two competing formats, manufacturers created hybrid drives that could read both – most hybrid drives that handle both formats are labeled DVD±R and Super Multi (which includes DVD-RAM support) and are very popular.

I hope this helps you to understand the difference between +R and -R DVD's.

Cheers mate!
The Doctor Cool

jovejupiter · Joined: Dec 12, 2004 Posts: 133

Thanks for the info.

I'd always assumed that DVD+R and DVD-R recorded the same data in slighly different ways, but as they're both rated as holding 4.7GB per disc I thought the differences were small. It seems that the differences are greater than I thought.

I've noticed that DVD+R discs seem to be more reliable than DVD-R discs and your post expains that.

Cheers

Tony

goretsky · Posted: Sun Mar 08, 2009 1:58 am Post subject:

Hello,

DVD+R and DVD-R discs use different technologies to allow the laser in the DVD drive to align and track its position relative to its position on the disc, these markings introduced into a recording are what uses up the additional space. This does not seem to make a difference as to how much can be recorded, though. A single layer DVD-R can hold 4.71GB of data, versus 4.70GB for a single layer DVD+R.

There's a great FAQ here which discusses the difference between the two different formats.

As to why we have two competing formats, well, pretty much for the same reason we have (or had) HD-DVD and Blu-ray: Consortiums of companies got together to promote (and generate licensing revenue) for each standard.

Regards,

Aryeh Goretsky