disc types

[photoman]

on the playes compatability chart there is 2 different columns on the types of dvd discs available. What is the difference between a DVDRW to a DVD+RW?? Anyone know the answer. I know that my HP internal will only burn the DVD+RW, CD-R, and CD-RW.

[DVD_Advisor]

DVD+RW, DVD-RAM and DVD-RW are all rewritable DVD formats, however, only DVD+RW is designed from the start to be compatible with existing DVD-ROM drives and DVD-Video players, both on a physical as well as a logical level. This means that a DVD+RW disc recorded in a DVD+RW video recorder can be played in virtually all DVD-Video players or DVD-ROM equiped PCs, and that any DVD+RW disc recorded with data on a PC DVD+RW drive can be read by most DVD-ROM drives.

The other formats do not offer this level of compatibility, or only provide for a very limited "compatible mode". For example: with DVD-RW video recorders you can only record 1 or 2 hours of video in compatible mode because it does not support lossless linking to allow for variable bitrate, and it does not offer the possiblity to write menu screens on the disc in a DVD-Video compatible manner. Furthermore you have to decide to use this setting up front, you cannot make a non-compatible recording DVD-Video compatible afterwards. The compatible mode does not offer editing features, and it requires the disc to be "finalised", which takes from 5 to 15 minutes minutes. Furthermore, the physical disc format of DVD-RW differs from DVD-Video in such a way that even in compatible mode it can only be read by less of existing players.

DVD-RAM uses a totally different kind of physical recording method, which is absolutely incompatible with DVD (hence, it can hardly be called 'DVD'). No existing player will be able to read DVD-RAM discs, even if you use the newer version without a cartridge housing.

For a comprehensive comparison between DVD+RW video recorders and DVD-RW/DVD-RAM video recorders in "compatible mode", please refer to the video recording comparison article. DVD+RW PC drives are compared with the rival formats in the PC drives comparison article.


How is DVD+R related to DVD-R?

DVD+R (DVD+Recordable) is defined as a subset of DVD+RW. Using dedicated DVD+R write once discs, which will be substantially cheaper than DVD+RW discs, users can record material in the same way as with DVD+RW discs without the ability to erase the disc or re-record onto them. DVD+R discs can be recorded by DVD+RW devices, first generation devices might need a simple firmware upgrade. DVD+R has the same characteristics as DVD+RW (exept for the ability to erase or re-record), such as the high degree of compatibility with existing DVD-Video players and DVD-ROM drives, the same storage capacity of 4.7 GB and the same usage applications. DVD-R was originally mainly targeted at authoring applications, and was not optimized for consumer usage. Therefore, various formats ('General' and 'Authoring'), sizes (3.95 GB and 4.7 GB) and versions (1.0, 1.9, 2.0) of DVD-R exist. As with DVD+RW, there will only be one format of DVD+R discs, which are usable in both video recording and data applications.


How is DVD+RW related to CD-R/RW?
Today, CD-R and CD-RW are widely in use as low cost storage media for data and audio applications, and will remain so for many years to come. DVD+RW will be used both in data storage (PC) and video (consumer electronics) applications. In the long term PC CD-R/RW drives will be replaced by PC DVD+RW drives, since these can do anything a CD-R/RW drive can, only faster and with a much higher capacity. Moreover, most PC DVD+RW drives will also be able to write to and read from CD-R and CD-RW media. In the field of audio recorders I expect that CD-Recordable Digital Audio will remain on the market for many years to come, since there is a huge installed base that can play home-recorded CD-Rs. Furthermore, DVD+RW has no audio-only application to date.

[vitualis]

however, only DVD+RW is designed from the start to be compatible with existing DVD-ROM drives and DVD-Video players, both on a physical as well as a logical level. This means that a DVD+RW disc recorded in a DVD+RW video recorder can be played in virtually all DVD-Video players

Well this was the hype but the reality is quite different. The compatibility of DVD+RW is no better or perhaps even worse than DVD-R.

As for the other stuff posted above, that is only relevant for stand-alone hardware recorders. It has no bearing if you author and burn a DVD on your PC.

Regards.