The Annoyance:

I’m writing to a 4.7GB DVD-R, but I only see 4.38GB of free space. What gives?

The Fix:

Ever work with hard drives? Well, hard drive vendors often use “decimal” gigabytes (1,000,000,000 bytes) to denote capacity, while software makers apply “binary” gigabytes (1,073,741,824 bytes). So, when you examine the disc with a typical software utility, a 4.7GB DVD disc may actually appear to have just 4.38GB (4.7/1.073) of space available. There is no “missing” space-it’s simply a different way of expressing the disc’s capacity.

Remember that a small percentage of the recordable DVD is set aside for overhead, such as link blocks, track information, video title areas, and so on. It typically consumes about 1MB of disc space.


The Annoyance:

Why do I get “Cannot recover from PMA” errors with my new media?

The Fix:

Each time you insert a disc into the drive, it checks and calibrates the laser power in the disc’s Power Management Area (PMA). If the drive can’t discern the appropriate laser power settings, it returns a PMA error. In many cases, the media is defective or unsuitable for the drive. Rewritable discs may simply be worn out (from being rewritten so many times). In either case, try a fresh, brand-name disc that meets the drive manufacturer’s recommendations.

If the problem persists, the drive may have trouble calibrating power for a particular brand of media. Check with the drive manufacturer for any firmware upgrades that ...

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