Standard single-layer recordable DVD disc is able to store an hour of footages at the highest quality setting. Image and sound quality are still very good if you extend to two hours – compatible with standard definition TV broadcast quality. Some recorders can record at variable speed (VBR) during the recording from digital TV. This matches the quality of the programs of TV broadcast (data rate) to the DVD recording data rate and therefore offers the most effective use of the available space.
You can increase capacity to record three, four, or even eight hours of footage on a disk, but image quality becomes lower and lower. Relative to single-layer disc, dual-layer discs can double the recording capacity.
We have introduced DVD+R, DVD-R, DVD+RW, DVD-RW, DVD-RAM in What DVD Formats Are Recordable and next we will introduce BD-R and BD-RE to you.
Blu-ray discs (BD-R and BD-RE)
There are two formats of Blu-ray disc capable of recording high-definition programming when used in a Blu-ray recorder. BD-R discs are write-once-only discs whereas BD-RE discs can be recorded on over and over again. These offer typically 6.5 hours of high-definition (HD) quality and between 10 and 13 hours of standard definition (SD) quality. However, both types are also available in dual-layer (DL) formats that offer twice these recording times.