Motion Picture Herald (Jan-Mar 1932)

46 Better Theatres Section February 13, 1932 The Perfect Screen Lens Adaptable to Any Projector The construction of this lens, deviates radically from all previous types heretofore known and is guaranteed to increase the illumination and greatly reduce your electricity expense on projection. The very long over-all length permits the rear lens to come as close as possible to the gate and therefore gather all the light rays. USED BY LEADING THEATRES EVERYWHERE Projection Optics Co., Inc. 330 Lyell Ave. ROCHESTER, N. Y., U. S. A. Heroes Must Not Lisp! Projection apparatus must not fail! That's the reason for the swing to Garver Units. GARVER KURRENT CHANGER The ideal rectifier for improving low intensity mirror arc projection. Elimmates Change Over Trouble Changing alternating to direct current, it unfailingly delivers 15 to 30 amperes of constant pure, white light at 20-30% saving. Most quiet, sturdy, simple unit made. No interference with sound. Recommended by leading lamp manufacturers. $150 complete. Get More Brilliant Mazda Projection with Less Current THE NATIONAL REGULATOR Small, compact, sturdy, simple, quiet, dependable. Ideal for spot and flood lighting and where highly concentrated beam is required. For cither 110 or 220 volts. $80 complete alt principal cities. I< iprescnlalives in GARVER ELECTRIC CO , UNION CITY ItslOI ANia while it might be true of a very large converter, it is not true for capacities used in projection work, where the smaller sizes will show 10% higher efficiency at full load ; and, since the load consists of only one lamp most of the time, the comparisons at one-half to two-thhirds load are so much in favor of the converter that we guarantee an average saving of \Qfo on sizes commonly used. "The inherent characteristics of converter to come, in step, either polarity does not make it an 'unstable piece of apparatus' when the polarity can be corrected by simply pushing a button or throwing over a switch. It takes only five seconds to bring our converter into step, and allowing five more for correcting polarity, where is the motor-generator set that can be started and d c. voltage adjusted to proper point in ten seconds? "While it is true that the d.c. voltage on a converter follows the a.c. variation^, it has never been a handicap for the reason that the power companies regulate the'"'line voltage within close limits and will gladly correct any serious line drop when called to their attention. Projection has always been good in the downtown direct current districts of large cities where the current is supplied through converters. The line drop has not bothered in either case, and the automatic arc feed has made the small variations unnoticeable. The converter has the advantage of a fixed voltage, hot or cold, whereas a generator automatically drops its voltage while warming up necessitating adjustments of the voltage during this period." FILM SCALES • A scale to show at a glance the approximate footage and length of time necessary to project the regular show and trailers, has been brought out by King Cole's Entertainment Service, Inc., of New York. The scale has a small slide which rests upon the rim of the reel, while the scale itself is pushed down until contact is made with the film. The reading at the point of the slot on the slide gives the approximate footage and the running time at 90 feet per minute. SHIPPING SCREENS • Some extremely useful information of quite surprising nature came the other day from the Beaded Screen Corporation of New York, and it is herewith passed along — particularly because it seems to represent real investigation in an effort to be of utmost service to the purchaser of screens. Here 'tis: " ^Sliip fast freight'. As far as Ave can ascertain, there are only two railroad lines that actually handle fast freight shipments, and tlien only over their own lines. It is a notorious fact that there is little if any difference in the time required for delivery between fast freight and ordinary freight. " 'Stiip via ( ) Forwarding Company'. A shipment made this way must be delivered by us to New York City for which a charge varying from one to three dollars is made. Except where the consignee has personal contact with the suggested forwarding company, this method of shipment does not expedite delivery. " 'Ship freight' . Freight is the slowest of all methods of shipment. It is impossible to determine the length of time a freight shipment will take as the variation in time runs from one to two weeks. " 'Ship by l>oat' . Goods shipped by boat, unless packed for export, are liable to var}'ing conditions of moisture and dryness. It is the riskiest of all methods of transportation for an article as fragile and delicate as a sound screen. "Comparative Costs. We have shipped thousands of screens all over the world, and know from experience the safest, quickest and most economical method of shipment. "The freight tariff for motion picture screens is double first class freight rate. We must deliver from our factory to the freight yard at this end. Then there is the cost of delivery from the freight yard to your door at your end. We find that these trucking expenses at our end and at your end run from $2.00 for a 9x12 screen to $4.50 for an 18x24 screen. "We have invariably found that the express rate for door to door delivery is less than the combined freight and trucking cost. The time of delivery is certain in the case of express. Within a radius of 300 miles from this factory, express delivery is made within thirty hours from the time of shipment. To all other points, the time required for transit is about one day longer than the time required for passenger transportation to the given destination. "An average size screen, shipped by express, will cost approximately $2 for door to door delivery within the 300-mile zone. Outside of that zone, the cost averages 75c per 100 miles." CANE ACOUSTIC TILE • A cane fibre type of acoustic tile has been developed by The Celotex Company, manufacturers of Acousti-Celotex, of Chicago. This tile is made from felted cane fibres and is perforated with 441 holes per square foot. The U. S. Bureau of Standards gives the sound absorption coefficients for the three classes available, as .08, .15 and .18 for 128 frequencies; .18, .24, and .33 for 256 frequencies; .48, .62 and .84 for 512 frequencies, these indices becoming more equal until they reach .81, .74 and .57 for 4,096 frequencies — reversing the order noted for the smaller number of frequencies. The tile is classed according to thickness as single, double and triple. BY WAY OF NEWS • C. F. Hussey, former manager and mechanical engineer for the Precision Machine Company of Milwaukee, has joined the Motion Picture Machine Company of the same city, as acting engineer. The latter organization manufactures gears, sprockets, rollers, etc., for Simplex and Powers projector heads.