Motion Picture Herald (Mar-Apr 1947)

Series II Speeds up to f/2.0 in focal lengths up through 5". Coated lenses. Hermetically sealed mounts. Features come and features go-some with stars, some with unknowns. But with SNAPLITE lenses in your projectors you are assured a star performance every time. Gone are dim images . . . fuzzy outlines . . . annoying color fringes. Instead— brilliant images . . . crisp outlines . . . sharp contrast! There are SNAPLITE lenses for every projection need— all produced to the same exacting standards of quality and precision. K 0 L L ii\0 KIplpB / 9 \ck {^Amcac CORPORATION 2 Franklin Avenue Brooklyn 11, New YOUR ASSURANCE THE BEST! WENZEL "SMOOTH-RUNNING" PROJECTOR You are assured of "Smooth-running" performance with the Wenzel time-proven projector. See Wenzel for precision replacement parts . . . your present equipment will do a smoother running job. WENZEL PROJECTOR 2509-19 S. STATE ST. COMPANY * CHICAGO 16, ILL. f just as well, but I also can recall a lot of cases where friction is high due to the poor allocation of work. I know the system suggested here works. What are your views on this subject? Port Glass Transmission And Light-Up Time A letter from Harry Lee of Calgary, Alta., Canada, raises a question that should get a "raise" out of some of you fellows. Here it is: "I would like your opinion on two questions. All over the city the lens port glasses are perpendicular with the lens. 1 notice on the back wall of our projection room a perfect picture is reflected from the port glass, proving to me that quite a lot of light is not getting to the screen. If this glass were put on an angle, the rays would strike the glass at different lengths, thereby breaking up the light beam when striking the smooth surface. It wouldn't distort the picture any as all rays would travel the same distance and finish with a flat field on the screen. "Our light-up signals are half a minute. The boys tell me it is too short. By the time you have trimmed the arc and got in position your eyes are more alert and not tired watching for the cue, result perfect changeover. One minute you are standing looking for the cue seems like an hour — you get restless, your eyes get tired and you are liable to blink just as it is going by, missing the cue." Brother Lee has submitted, first, a question that could be answered in just a few words if he would like to accept my say so, but there have been many words said pro and con on this matter. I will try to give some of the reasons both for and against. PORT GL4SS EFFICIENCY First, port glass, if of the best optical glass, will cut light about 5%. If glass is used in the ports, it should be cleaned before every show. Dust that collects on the front surface will decrease light still more. A poor grade of ordinary window glass will cause picture distortion. If you are using the glass to cut your booth noise, why don't you use baffles in your port openings? You can use any type acoustical board. Cut an opening in the first one just large enough for the rays from the lens to pass, and increase the opening in each succeeding one enough more to accommodate the expanding beam. You can use as many as you see fit. (I do not allow any optical glass to be used in my situations.) I have always felt similarly about the degree of angle for port glass, but from all reports it works the same either way as far as light transmission is concerned. BETTER THEATRES, APRIL 5. 1947