8mm/Super8mm: Amateur format. Many collectors started with 8mm, then “traded up” to 16mm and/or 35mm. Companies like the defunct Castle Films are still fondly remembered for their 8mm and Super8mm reductions of classic comedies and Universal horror films.
16mm: A “prosumer” format, mostly used for homes, hospitals, schools, and other institutions, film clubs, TV broadcasting, and nontheatrical rental libraries. Historically, this was the format of choice for most collectors: 16mm prints were more readily available, projectors were much easier (and cheaper) to own and operate, and prints easier to store.
35mm: Standard commercial theatrical format for film projection for most of cinema history. A minority of film collectors collect 35mm, mainly due to the increased cost and complexity of owning and operating 35mm projectors, and the much larger “footprint” it takes out of one’s home.
70mm: Visually spectacular, high-resolution large format commercially introduced with the release of Oklahoma! in 1955. Expensive to make and develop, 70mm was reserved for event movies like West Side Story (1961), Lawrence of Arabia (1962), and The Sound of Music (1965). Very few collectors specialized in 70mm, because of the cost of projectors needed to screen properly, and the enormous size and weight of the prints. Seventy-millimeter prints were never struck in IB Technicolor, so almost all original prints from the 1950s to the 1970s have faded badly (although later 70mm prints from 1982 onward were struck on low-fade LPP stock).
Blue-track Technicolor (16mm only): Late 1940s/early 1950s method of printing soundtracks on 16mm film; contrasted with the normal “grey track” method, which was more expensive and used for 35mm. By the early fifties, Technicolor started doing 16mm in the “grey track” method as well. Blue-track prints frequently had fuzzy sound and would not play at all on some projectors.
CineColor/SuperCineColor: Another form of dye-transfer printing, not done by Technicolor. Holds its color, though can look a bit odd. Both 16mm and 35mm have blue soundtracks.
Dirty dupe (aka: Reversal dupe, auto-positive): Positive print made from another positive print without making a negative first. Such prints tend to have contrast issues.
Dupe: A copy; not an original print. Generally made by a “bootleg” film lab, using an existing positive 16mm print. A duplicate negative is made, from which positive prints (“dupes”) are struck. The quality of these can vary widely, depending on a variety of factors. For example, some labs used positive film stock (which was cheaper) to make dupe negatives instead of regular negative stock. Some labs rerecorded the soundtrack; others did not.
Eastmancolor: Various color stocks that are NOT IB Technicolor are referred to by collectors as “Eastman prints,” but not all are actually on Eastman Kodak Color stock. Eastman prints (or Fuji prints) printed before late 1982 are subject to film fade.
EK print (35mm): A print struck from the camera negative. Most prints are struck from duplicate negatives to save wear-and-tear on original camera negatives.
Film fading: Until late 1982 most non-Technicolor film prints were printed on “dye-coupler” stock (such as Eastmancolor, FujiColor, etc.). Colors that were printed “dye-coupler” can fade quite rapidly, sometimes in just a few years. In late 1982 the chemistry was updated, and dye-coupler films no longer fade (we hope). Prints done “dye-transfer” (such as Technicolor, CineColor, and others) had much more stable color. Such prints are prized by film collectors for this reason.
Film rejuvenation: Used motion pictures are cleaned using various chemicals and other means to make them “project like new” again. Scratches and dirt are removed and “filled in” so that they don’t show when projected. Unfortunately, many scratch-removal processes cause the film to “go vinegar” rather quickly; film collectors tend to avoid prints that have been “treated” for this reason.
Four-track magnetic sound (35mm) and six-track magnetic sound (70mm): Now-obsolete sound formats that in their prime offered superb multichannel stereophonic sound in theaters. Prints were striped with magnetic sound tracks to the side of the picture frame. Four-track offered left-right-center full range tracks with a monophonic surround. Six-track offered left, left extra, center, right extra, right, and surround.
LPP (Low-fade Positive Print): Kodak prints struck after late 1982 that are (at least theoretically) “non-fade.” So far, that appears to be the case. Fuji released its own version: Fuji LP stock.
Nitrate film stock: Original nitrocellulose film stock, made until about 1950. Known to be quite flammable, especially when starting to decompose. Made only in 35mm.
Original print: A print made from the original printing elements (usually by the studios). Original prints have a much better “look” than copies made by bootleg film labs.
Projection booth terms:
—Carbon arc: Original method used in professional 35mm projection. Two carbons are spaced very slightly apart; then a very high voltage is applied, causing a very bright “arc” to form. The carbons are kept a specific distance from one another as they burn. The projectionist must replace the carbons after each twenty-minute reel is shown.
—Xenon bulb projection: The “modern” method of showing film. Although they last much longer than carbons, the xenon bulb must still be replaced by a professional periodically, and they are very expensive bulbs.
—DCP projection: The new digital method (no more film!) of showing movies in theatres. DCP stands for “Digital Cinema Package.”
Reduction dupe: The bootleg lab uses a 35mm release print (instead of a 16mm print) to make their duplicate negative. These generally look far better than dupes made from 16mm, but again, quality can vary widely.
Safety film stock: Triacetate film stock. Invented in the 1930s, but not in wide use until about 1950 (for 35mm). Was used in 16mm earlier, however. Safety stock can decompose but is not flammable.
Technicolor (or “Tech”): The gold standard for color prints. Generically called “IB Tech” (short for Imbibition Technicolor); also referred to as a “3-strip print” or “dye-transfer print.” Technicolor prints are renowned for holding their bright vibrant colors and not fading. Dye-transfer printing has not been done in the United States since 1974 (with a very brief exception when Technicolor brought it back in the late 1990s).
Vinegar syndrome: When acetate safety stock starts to decompose, it starts to smell like vinegar (the smell is actually acetic acid). Film that’s “going vinegar” starts to shrink and ultimately can turn to brown dust (which still smells like vinegar!). Vinegar syndrome will happen to all acetate safety film over time, but the two worst factors that accelerate this are heat and moisture. Film should therefore be kept in a cool, dry place for long-term storage.