As one of the most helpful technological marvels of the 21st century, DVD RW technology makes it easy for video enthusiasts to burn their own discs. From home movies to professional films, these discs hold a range of entertaining footage. Even better, they are also perfect for data storage. DVD RW technology is relatively straightforward, but users need to understand a few basics.
The Surface of a DVD RW Disc
Every DVD features a mirrored surface. This mirror has a series of bumps that read as code. Using the code, DVD players take the analogue information and transform it into digital output to create images on screens. However, on a DVD RW disc, no bumps are present. In addition, a blank DVD RW disc features a film coating that accepts bumps when the user writes the disc and also erases the bumps. This is what allows the rewriting of the discs.
A Typical DVD RW Disc's Capabilities
A standard blank DVD RW disc holds two hours of video on each side or up to 4.7 GB of data. Many movies are longer than two hours, and that makes it necessary to change discs when burning videos that are longer than 120 minutes. It is possible to find Maxell DVD RW discs that are writable on both sides to make life easier for the user. Most discs feature write speeds of 1x to 2.4x, which is in line with most modern DVD writers.
The DVD Writing Process
DVD recording takes place using a laser system. The thermal laser pulsates against the disc and imprints the image to allow the DVD player to read it later. Each bump the laser creates exists in a continuous track, which is why users who look at DVDs closely can see a series of circles making their way from the middle towards the outside. When the time comes to play the DVD, the DVD player uses another laser to read the bumps. This optical sensor then transforms the bumps into a digital format that creates the images for the screen. During this process, the DVD player's laser follows the circle from the centre to the outside in the proper movie playing sequence.
Erasing a DVD RW Disc
In a manner similar to the writing process, a laser also erases the data. Using PCs and laptops, it is possible to erase single files or entire discs. When using discs for data storage, users can easily move single files from folder to folder or completely erase them. Movies are typically large individual files that require moving and erasing in their entirety.