a free souvenir, were die-cut in the shape of a 1939 Plymouth seen head-on. Their Polaroid filters, stapled over rectangular openings where the headlights ought to be, were very small. Cardboard glasses with earpieces and larger filters were used to watch Bwana Devil, the feature-length color 3-D film that premiered on 26 November 1952 and ignited the brief but intense 3-D fad of the 1950s. The well-known Life magazine photo of an audience wearing 3-D glasses was one of a series taken at the premiere. The film's title, imprinted on the earpieces, is plainly visible in high-resolution copies of those images. Imaginatively colorized versions have helped to spread the myth that the 3-D movies of the 1950s were projected by the anaglyph color filter method. In fact, during the 1950s anaglyph projection was used only for a few short films. Beginning in the 1970s, some 1950s 3-D feature films were re-released in anaglyph form so that they could be shown without special projection equipment. There was no commercial advantage in advertising the fact that it was not the original release format. Polaroid filters in disposable cardboard frames were typical during the 1950s, but more comfortable plastic frames with somewhat larger filters, considerably more expensive for the theater owner, were also in use. Patrons were normally instructed to turn them in when leaving so that they could be sanitized and reissued, and it was not uncommon for ushers to be stationed at the exits to attempt to collect them from forgetful or souvenir-loving patrons. Cardboard and plastic frames continued to co-exist during the following decades, with one or the other favored by a particular film distributor or theater or for a particular release. Specially imprinted or otherwise custom-made glasses were sometimes used. Some showings of Andy Warhol's Frankenstein during its 1974 U.S. first run featured unusual glasses consisting of two stiff plastic polarizers held together by two thin silver plastic tubes slit lengthwise, one attached across the tops and bent at the temples to form earpieces, the other a short length bent in the middle and serving as the bridge piece. The design managed to be both stylish in an appropriately Warholesque way and self-evidently simple to manufacture from the raw sheet and tube stock. Linear polarization was standard into the 1980s and beyond. In the 2000s, computer animation, digital projection, and the use of sophisticated IMAX 70 mm film projectors,