Are green CD-R discs better than gold or blue ones?
This is an excellent question. Unfortunately, color is not a useful CD-R quality indicator. The human eye sees color in the visible portion of the light spectrum, while CD-R lasers operate in the infrared part of the spectrum. Only the interaction between the infrared laser and the organic polymer dye layer is important to quality, not visible color such as gold or green. Read lasers operate at a very low power level that does not alter the dye. Writers switch laser power to much higher levels that alter the dye during recording. The matrix of CD-R dye types, writers, firmware revisions, and recording software are far more complex than for CD-ROM discs. CD-R discs first used a cyanine dye developed in Japan by Taiyo Yuden. Discs initially had longevity problems until stabilizers were added. Current products have good longevity. The blue color of this dye and the gold reflective layer combine to produce an emerald green or blue-green color. A relatively high laser recording power of 6.5
• Do gold CD-R discs have better longevity than green discs? • Rumors state that silver CD-R discs can damage the lasers in drives. Do blue CD-R discs with silver metallization have the same quality as gold? • I am told by some suppliers that all CD-R discs are the same. Others tell me that gold discs are the best, another states that blue discs are of the highest quality, and some say that silver is unacceptable. What discs are best? • How are Grade A, Grade B, and Grade C CD-R discs defined? Are they all usable? • What are “audio” rated CD-R discs? Are they of higher quality? • The manufacturer of my 48X CD-R writer states that media used in the writer must be 48X certified. Is this just an attempt to control my choices of media? • I always buy high capacity, 74 minute CD-R discs. Why would anyone use discs with only 63 minute capacities? • Where can I find the new 90 minute CD-R discs? Why were they previously unavailable? • Tests of blank floppy disks can assure quality. Why not do
