Whether you are working with a computer for productivity, for photography or video editing -- you are likely going to use a disc* for importing materials and also for exporting the finished program. This may change in the coming months and years as new forms of solid state media are becoming all the rage.
But since discs are still the common form of storing, transferring and distributing data, media and programs I thought I would pass along the following information as to how much data you can fit onto one of the common disc formats:
- CD = 700 MB (MegaBytes)
- DVD = 4.7 GB (GigaBytes)
- DVD-DL (Dual Layer) = 8.5 GB (GigaBytes)
- Blu-ray = 25 GB (GigaBytes)
- Blu-ray DL = 50 GB (GigaBytes)
By the way - not all discs are created equal. The discs you can get on sale at the local warehouse store is not something I recommend you use. You spend hours working on a project, it is worth your investment to work with a higher quality disc... this is particularly true and important when producing DVDs. There are cheap discs that you and I can purchase that have low or no quality control. They may result in DVD failure -- I have spoken with colleagues over the years who have experienced this. Stick with a quality, industrial brand name product.
I work pretty much exclusively with Taiyo Yuden DVDs and choose to purchase them through the good folks at CAM Audio, Inc. in Dallas, Texas. They have quality product at reasonable prices (you purchase the discs in spools of 50 or 100). You can download a catalog from CAM Audio here -- and you can visit them on the web at www.CamAudio.com or you can call them at 866-364-1317. They sponsor another website I produce but I choose to purchase all my product from them... good folks!
* The difference between disc and disk.
Discs
A disc refers to optical media, such as an audio CD, CD-ROM,
DVD-ROM, DVD-RAM, or DVD-Video disc.
All discs are removable, meaning when you un-mount or eject the disc
from your desktop or Finder , it physically comes out of your computer.
Disks
A disk refers to magnetic media, such the disk in your computer's hard drive, an external hard drive. Disks are always rewritable unless intentionally locked or write-protected. Disks are usually sealed inside a metal or plastic casing (often, a disk and its enclosing mechanism are collectively known as a "hard drive").
Thanks to this Apple Support Article for the difference between the c and k
Good point David -- I understand as well that the actual capacity can vary ever so slightly between disc manufacturers (still within standards but could be confusing to someone who watches the precise capacity between different brands of optical media).
Posted by: Chet Davis | 10/30/2009 at 09:58 AM
Don't forget that you lose some capacity due to formatting on a disc (just as you do on a hard drive - ever notice that your 500GB computer hard drive only shows as 465GB?), so all of the space on a disc isn't really available. The use-able space on a 4.7GB DVD-R, for example, is actually more like 4.2-4.3GB.
Posted by: David Adame | 10/30/2009 at 09:28 AM