The motion picture projectionist (Nov 1931-Jan 1933)

34 Motion Picture Projectionist October, 1932 Efficiency in Illumination IN these days of economizing and retrenching, it is surprising to find that comparatively little attention is given to the factors involved in the correct illumination of the motion picture screen through the projected picture. For here is a phase of projection which, if ignored, may often result not only in failure to secure the best results from all parts of the equipment, but also in extravagant waste cf current. This criticism is by no means confined to the smaller and often inadequately-staffed houses. As a matter of fact, some of the present outstanding examples of inefficient illumination exist in up-to-date and flourishing theatres, where one might expect to find the expert attention that their fine equipment deserves. From the point of view of projection alone, and so far as the member of an audience is concerned, the projected picture may be regarded roughly as an illuminated photographic enlargement. And as the excellence of a photographic enlargement depends largely on the quality and grain of the paper used, so is the motion picture enhanced or marred by the reflecting quality and texture of the screen upon which it is projected. It became apparent in the earliest days of motion pictures that an opaque surface would have to be substituted for the reflective sheet inherited from the magic lantern. The introduction of that opaque surface was the beginning of much controversy as to what constituted its ideal quality, and of a line of secret processes, patents and fantastic claims that ended only with the coming of talking pictures. The outstanding advantage played upon by the manufacturers of the opaque screen was its negligible amount of light absorption resulting in more brilliant illumination with minimum consumption of current. Electric current reductions claimed by some of these manufacturers ranged as high as 60 per cent. "Talkies" Bring New Problem . When talking pictures emerged from the laboratory, the necessity for placing loudspeakers behind the screen as a means of aiding proper distribution of sound presented a new problem in screen manufacture. First, woven screens were devised. It was fully evident though that with, the THEATRE EQUIPMEM f£, ^-^ NEW AND USED \ ' -j_l Sound Equipment, Moving Picture Machines, Screens, Booths, Opera ^t. Chairs, Spotlights, Ster"^j eopticons. Film Cabinets, y Portable Projectors, M. || P. Cameras, Generator I | Sets, Reflecting Arc 3 Lamps, Carbons, Tickets, Mazda Lamps and Supplies. Projection Machines repaired and overhauled. Repair parts for all makes opera chairs. Attractive 3x10 ft. muslin banners, $1.50 : on paper, 50 cents. Wc Pay Highest Prices for Used Projection Machines, Opera Chairs, etc. ETtrytbisi for the Theitre — Write for Cattlor K. MOVIE SUPPLY CO.. 844 So. W.haih. Chic.no. . relatively little opaque quality of the woven screen, great increase of light absorption and consequent prohibitive current consumption was inevitable. Nor was that the only disadvantage. It was equally apparent that an openweave surface would act as a trap for every particle of foreign matter in the auditorium's atmosphere, necessitating frequent cleaning of the screen. The Perforated Screen Then was realized the simple possibility of retaining the essential advantages of the opaque screen and providing at the same time much more adequate sound passage than hitherto possible. This was the so-called "rubber" screen. The rubber screen was a material surfaced by opaque treatment to give it a desirable reflectivity of projection light. The passage of sound in this screen was provided for by perforating the fabric with numerous minute holes in regular or irregular formation. This combination resulted in ample passage of sound and in a great saving of light absorbed from the projector. But no idea, simple or otherwise, has yet been born perfect. It was soon found that unless the holes were cleanly cut in the fabric the frayed edges would in a short time collect enough dirt to affect seriously both the projection quality and the passage of sound. Moreover, the material used was not strong enough to withstand the weakening due to the cutting of the perforations and there followed the appearance of unsightly lines on the screen's surface. It is interesting to note that in spite of their shortcomings a considerable number of these screens, including many of the old type fabric screens, are still employed. In many parts of the country the use of the fabric screen is now prohibited. One would think that apart from its ininefficiency, the expense and inconvenience of maintaining one of these screens would alone prohibit its use, for it must be sent away frequently for cleaning and fire-proofing. The modern properly-woven and cleanlyperforated screen on the other hand, besides conforming to fire regulations everywhere, may be cleaned as it stands. Degree of Light Intensity Just as excessive current, in a vacuum tube not designed to cope with it, results in distorted sound reproduction in the loud-speaker, so excessive illumination of the screen is a cause of bad projection. Ample but not excessive illumination from the arcs is, therefore, a matter deserving of more than casual attention. Circumstances, no doubt, determine to a large extent, what degree of illumination is best suited for a particular house. However, it is safe to say that it is a mistake in a theatre where throw and screen area unmistakably call for high intensity to try to get adequate performance out of a low intensity lamp. The manufacture of the projection carbon has been carried by research to such a state of perfection that today— to draw a somewhat frivolous comparison — as there is a lipstick to match every known complexion, so is there a specific and essential type and combination of carbons to produce the best results for every condition of installation. The benefit derived by the correct use of carbons is common to both the manufacturer and the theatre. Mirrors and Lenses Another cause of inefficient lighting is the presence of a "dark spot" or other blemish due to inaccurate focusing of the mirror with the other components of the optical system. The replacement of the existing mirror by one not originally designed to fit the lamp is a common cause of this. The projectionist who knows his job will soon remedy the defect by means of a little experimenting, or if proper adjustment proves impossible, insist on a mirror purchased from the manufacturers of the lamp. Frequent damage to the mirror from flame-lick in the case of projection at steep angles, may be simply and inexpensively remedied by the use of an arc flame control. Though this may be home-made, most projectionists will prefer to purchase it since the cost is quite moderate. It is almost unnecessary to point out that good projection depends largely upon the type, proper design and quality of the lenses employed. Yet it is a fact that many an exhibitor who does not hesitate, to spend money on the latest luxury in automobile equipment will balk at the prospect of any financial outlay to modernize the equipment upon which his livelihood and prosperity depend. Moreover, there is many a projection-room in which upto-date equipment would, in the saving of current alone, pay for itself in twelve months. Academy Nominates Officers Nominees for offices in the Academy of Motion Picture Arts and Sciences for the coming year were announced today. The annual election of the organization will be held October 15. Following are the nominations: For the Board of Directors : Actors' Branch, Sam Hardy; Directors' Branch, John Cromwell; Producers' Branch, B. P. Schulberg; Technicians' Branch, J. Theodore Reed; Writers' Branch, Oliver H. Garret. Members of the Board serve three year terms, the expirations being on a rotating basis so that one vacancy in the representations of each of the five branches is to be filled each year. For the Branch Executive Committees: (One year terms). Actors' Branch — Edward G. Robinson, Chester Morris, Warner Baxter, Reginald Barlow and Hedda Hopper. Producers' Branch — L. B. Mayer, B. P. Schulberg, David Selznick, Winfield Sheehan and Jack Warner. Directors' Branch — C. B. deMille, Alfred Green, Robert Leonard, Rouben Mamoulian and Fred Niblo. Technicians Branch — Hans Dreier, Nugent Slaughter, J. M. Nickolaus, John Arnold and I. James Wilkinson.