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1952 Theatre Catalog, 10th Edition, Page 300 (264)

1952 Theatre Catalog, 10th Edition
1952 Theatre Catalog
1952 Theatre Catalog, 10th Edition, Page 300
Page 300

1952 Theatre Catalog, 10th Edition, Page 300

FIG. 28. Examples of cue marks found in release prints.

low the emulsion side of the film to rub against metal surfaces. The sound synchronization is also affected by an oversize intermittent loop. On the other hand, the loop must be large enough to prevent the possibility of binding.

Toke-up Tension

The take-up adjustment should be checked from time to time to avoid unnecessary damage to the hold-back edges of the perforations. Excessive pulling at the hold-back sprocket can be detected by a pronounced itsinging" sound and might be caused either by oil on the friction disc or by improper spring adjustment, particularly on older type equipment. If the tension is too great, as is often the case when adjust FIG. 27. Sprocket tooth denting or "roping."

ments are made to avoid the possibility of loose winding at the end of a large roll, serious damage to the hold-back edges of the perforations in the first part of the roll may occur.

The hold-back sprocket should be checked occassionally for any signs of premature wear. If such wear is found, the take-up tension should be examined and ire-adjusted to minimum setting for correct winding.

Automatic Rewinds

Automatic rewinds should be checked for proper alignment. If the flanged and tracked control roller is cocked slightly either vertically or horizontally, undue strain will result on one edge of the film, particularly if the tension is excessive and if there is binding against a bad reel flange.

Hand winding, however, seldom gives the smoothly wound roll obtained by motor winding unless the film is correctly guided to the reel. Film edges which protrude from the reel after poor winding usually break off in small or large sections when the roll is forced into the case, or during shipment, (See Figure 25.)

Cue Marks

A considerable portion of the film mutilation which admittedly occurs in the projection room is due to the Various types and sizes of cue marks at the ends of rolls. In many cases, these are so carelessly done that large portions of the picture area are affected. Two, three or more sets of marks are not uncommon and they consist of punch marks, lacquer bands, large cross lines and scratches of every description. Examples taken from theatre prints are shown in Figure 26. These are but a few of the marks commonly encountered and many which have been found are considerably worse.

As stated before, considerable loss of footage is caused by the end of the film whipping around on the rewind or projector take-up before the roll can be

stopped. This makes it necessary to place new cue marks on the film, but it is not necessary to have an elaborate assortment of marks. Many projectionists cover at least some of the unwanted marks with narrow strips of adhesive tape, but these strips must be checked for tightness as they have been known to peel off and become lodged in the magazine valve rollers. On the other hand, when unwanted cue marks are removed, shortening of the end section results and this encourages placement of additional markings on the film later on.

Sprocket Tooth "Roping"

Sprocket tooth dents, often identified as 'troping" or "run-offs" by exchange inspectors, is also a consistent cause of film mutilation. These marks, shown in Figure 27, are commonly seen between the perforations and are also often found through the track and picture areas in a weaving pattern. A "runoff'i may start at a bad splice if the film jumps the sprocket, but it can also result from improper threading. Often the film becomes so weakened that subsequent edge bending causes the edge to break. The space between the rollers and the sprockets should be checked, and it is important to see that both rows of perforations are properly engaged with the sprocket teeth before clamping down the rollers.


Projectionists will recognize the type of damage shown in Figure '28 as that resulting from folding of the film in the sound head due to a break at this point. It is often erroneously referred to as ttbuckle" by the exchange people.

Edge Bending or Creosing

Projectionists are familiar with film bending through the perforations, or more often between the perforations and one edge, as shown in Figure 29. This type of damage, which is usually

FIG. 28. Fleeting.

1952 Theatre Catalog, 10th Edition, Page 300