The Difference Between DVD+R and DVD-R

What is the Difference Between DVD +R and DVD -R?

Is DVD+R the new Betamax? A small and easily overlooked difference in the naming structure of DVDR means a big difference technically, though most users will never notice.

DVD-R, known as “minus R” in Europe and “Dash R” in the US, was the first write once recordable DVD format and was developed by Pioneer in 1997. Although it came a year after the DVD RAM rewritable format it was the original recordable DVD designed for use in DVD video players and as such gained rapid popularity. Its 640 nm (nanometer) wavelength is narrower than the 780 nm wavelength of CDR and allowed for considerably more data to be squeezed on to a disc the same size as a CD. This additional capacity also helped the format gain popularity as not only a DVD Video recordable but also a 4.7GB data backup format.

Some 5 years later in 2002, a new format developed by the DVD+RW Alliance was released. The new format was named DVD +R (Plus R) and although it did not change much in terms of user experience or functionality, it did make some big technical improvements in terms of reliability of writing and reading the data. The refinements were based around increased better error correction, allowing data to also be written at higher speeds. The two formats are technically incompatible which means that a recordable drive that only supports the -R format will only accept that type of media (the inverse is also true). However the format war was mostly avoided as recordable drives rapidly became compatible with both formats, meaning the user is unlikely to notice the difference. The +R version was not initially approved by the DVD Forum (the official body that oversees the DVD format) and was seen as being incompatible with DVD technical specifications. However in 2008 the Forum finally accepted DVD+R and gave it the official seal of approval.

The five year lead that the -R format had over +R meant that even in 2010 -R is more prevalent in use and is also likely to be better value than the +R variant.
The exception to this is the DL (double layer format) which was launched in 2003 and provided nearly double the amount of capacity at 8.5GB. This allowed for the equivalent of a DVD9 replicated DVD to be recorded. Compatibility with DVD players is also greater with -R as until 2004 DVD players predominantly only supported this format. There are still legacy players which are not compatible with +R and therefore it is normal for DVD duplication companies to offer -R for single layer and +R for double layer copies.

To conclude, the +R format had the advantage of arriving later and being able to correct some of the design flaws in the original incarnation of the DVD recordable technology. As such it is a superior format having better error handling and writing properties. In much the same way as Betamax was a superior format to the more popular VHS, the technically inferior format has proved more popular. Thankfully the differences between the two are not as great as those between competing analogue tape formats and manufacturers have been able to manufacture equipment that is compatible with both variants, allowing the two to co-exist in the market.