What is the difference between a DVD-5, DVD-9 and DVD-10? What is a dual-layer disc?

DVDs come in different sizes. The numbers relate roughly to the amount of storage space they have, in GB.

They are:

• DVD-5 Holds approximately 90 mins of high-quality video & audio (4.7 GB)
• DVD-9 This is a "dual-layer" disc, and can hold about 3 hours of material (8.5 GB)
• DVD-10 This is a double-sided disc, and can hold up to 4 hours. (9.4 GB)
• DVD-9 tends to be more popular than DVD-10, partly because a DVD-10 requires the viewer to turn the disc over, and also because since both sides of a DVD-10 are played, they can't have artwork printed on the disc.

All the timings above are guidelines only. If you need several different audio tracks, for example, there may be less space for video. However sometimes it is possible reduce the data-rate of the video to "squeeze" more onto the disc. Depending on the type of material, this may reduce the picture quality, however. We'll always be happy to provide you with a free assessment of which size of disc will be best for your particualr project.

Dual-layer (DVD-9) discs can hold almost twice as much information as single layer (DVD-5) discs. As the name suggests, the data is split across two "layers". The player's laser refocuses to change layers half way through. This point is knowm as the "layer-break", and depending where it is placed, there may be a brief pause in the video playback as a result.