Boxoffice (Jan-Mar 1941)

CINE' CLINIC PRACTICAL DISCUSSIONS ON MODERN PROJECTION AND SOUND PRACTICES Defects in Motion Picture Projection and Their Correction ONTROL of the flicker evil has had much attention from the industry. Flicker caused by shutters, light fluctuation, and uneven photography has been investigated, and progress has been made on the elimination of each. But today there still exists an evil which has been with us since the first release print. It is the evil of oily film, which is becoming more and more noticeable through the adoption of more brilliant light-sources and high-key photography. It is essential to good projection that the film be clean, since every defect is highly magnified, and any deviation from perfect cleanliness is detrimental. Perhaps the most commonly recognized indication of oily film is the traveling “frame-line effect,” so noticeable with the high-key prints. A lighter area, the width of a frame line, starts from the bottom of the screen, and travels slowly to the top. This is surrounded by a darker flickering area superimposed over the entire picture. All oil patterns are not of such a well defined shape. They vary from frame to frame and depend in extent upon the amount of oil on the film at that moment. The pattern changes from one rewinding to another. It always shows on the screen as a crawling, spotty effect which may move from bottom to top as the “frameline effect,” or horizontally as a dancing effect. It may even appear as a wavering mass of flicker. If the film is light or toned, the effect is very pronounced, due to the contrast between the oil spots and unaffected areas. If oil is present on the film in a thick layer the image becomes blurred, causing an out-of-focus effect. This type of oily film shows a strong tendency to buckle under heating. The alternate sharpness and blur of the image, combined with “mass flicker effect,” are very tiring to the eyes, and with the long show times of double-feature bills, running from three hours upward, sets up a condition discussed by Snell, namely, “Anything causing difficult seeing will result in eyestrain.” The combined action of all the various types of flicker caused by oil spots, constantly changing position over a period of hours, most certainly must affect the eyes of the theatre patron and mar his enjoy by IRL GORDON* ment. Almost all films, after the first and second runs, have some oil on their surface. Various kinds of oil are used for lubricating motion picture projectors. Some are thin and fairly transparent; others are of a heavy, sticky automobile type used under the mistaken impression that they will cling to the bearings longer. When any oil is on the film, dirt, dust, and bits of grit are picked up and lodge along the path of the film in the projector, or cling to the rotary stabilizer drum of the soundhead thus constituting a prolific cause of scratches. If the emulsion with all this dirt, which acts as an abrasive, happens to “skid” while rewinding, fine scratches occur which soon fill up with dirt and show on the screen as a form of “rain.” Once oil is on the print, it is a difficult job to remove it without proper cleaning machines. The mere wiping of the film with a rag moistened with cleaning fluid will not do much good, since in a very short time the rag becomes so dirty it merely smears the accumulated dirt over a larger area. Very few theatres have installed cleaning machines. Film images may be classified broadly into four groups accordingly as they show oil spots, as follows: (1) The first and worst is probably the toned print, and the most seriously affected of this type is the brown toned film. Indeed if a liberal dose of oil is present, the result is so very annoying that it will detract from the dramatic value of the story in spite of concentration on the part of the observer. We have had many complaints of “something wrong with the picture,” when showing this type of print. “Frame-line effect” and “mass movement of oil” stand out very clearly. (2) The next is the print in the light or high-key, containing very light scenes, outdoor western shots, and scenes in which there are great areas of low density. “Frame-line” and “mass” effects predominate. Dirt and scratches show plainly. Cartoons are included in this group. (3) Color-film comes next. With some scenes, the oil causes a fuzzy appearance; on the lighter scenes “frame-line” and ♦Forum Theatre, Akron, Ohio. Reprinted from the Journal of the Society of Motion Picture Engineers, issue of June, 1940. “mass” effects are very annoying. In only a few instances, however, does the oil appear to change the color values. However, with the trend to lighter color prints the oil evil is becoming more troublesome, because on the dark prints of the past the oil spots did not show up so plainly as explained below. (4) Probably the least affected are very dark prints, in which even the highlights are grayed considerably. These are called “low-key” prints. Oil on this type shows only as a mass effect in the lighter portions of the scene, causing a wavering effect. The tendency for the emulsion to become scratched seems greater, which may be accounted for by the fact that the emulsion appears to be softer when much oil is present. If oil happens to be present in considerable quantity the image seems to change color. Dense prints are difficult to project in any event, and the addition of oil and dirt further reduces the brilliancy of the screen image. Some tendency to buckle has been experienced with oily dark prints, though this can not be stated as the general rule. Oil gets on film in various ways. A new print will begin to show signs of oil along the left side within a short time. With the new print, poor waxing or treatment before showing is one reason why the print is often “directly oiled.” A new print as received from the exchange has been either waxed or treated. The first time through the projector everything is fine. After three or four showings, however, trouble very often starts. Usually during the evening show on the opening day the print begins to stick. Late-model projectors have means for tension release, but tension has to be so loose that the screen image will jump, and rather than face a bill from the exchange for strained perforations or have a jumpy picture, the tension is eased up a little and oil is poured on the perforation track, which in successive runs spreads over increasingly large sections of the film. Quite a number of first-run projectionists have felt obliged to resort to this oiling practice at some time or other. As to the relative merits of the various film treatments with respect to preventing oil spotting I have no reliable data, but do know that sticking occurs with all of them on occasion. The most common path of access to the film is through contact of the film with oil in the projector mechanism, particularly near bearings or intermittents, and in sound-heads. Worn bearings, leaks at the intermittent and over-oiling cause oil to be smeared over the interior of projector and sound-heads, often causing pools of oil to be formed. Gears throw off oil which drains and seeps through crevices, often Have You a Problem? Conductors of the CINE' CT.INIC will be glad to answer questions relating: to problems of projection and sound operation and practices through these columns. State your problem clearly, detailing: symptoms of trouble. Answers to questions of general interest will be published in a later issue, identified by inquirer’s initials only. Should you desire private information or advice, enclose stamp for reply. Address The MODERN THEATRE, Room 334, 332 S. Michigan Ave., Chicago, III. 70 The MODERN THEATRE SECTION