DVD CDs (0.74 µm for DVD versus 1.6 µm for CD), accounting in part for DVD's increased storage capacity. In comparison, Blu-ray Disc, the successor to the DVD format, uses a wavelength of 405 nm (violet), and one dual-layer disc has a 50 GB storage capacity. Read and write speeds for the first DVD drives and players were 1,385 kB/s (1,353 KiB/s); this speed is usually called "1×". More recent models, at 18× or 20×, have 18 or 20 times that speed. Note that for CD drives, 1× means 153.6 kB/s (150 KiB/s), about one-ninth as swift. DVD-Video is a standard
Picture disc picture disc is "To Elvis: Love Still Burning", a collection of 11 Elvis Presley tribute songs by various artists, issued in May 1978. Both sides of the album (Fotoplay FSP-1001) picture Presley. On some picture discs, the images used were meant to create an optical illusion while the record was rotating on the turntable (as in the B side of Curved Air's "Airconditioning"), while others used the visual effect to add to the music — for example, the 1979 picture disc of Fischer-Z's "The Worker" featured a train which endlessly commuted around the turntable, reinforcing the song's message. Later picture