Movie Makers (Jan-Dec 1953)

212 LETS SHOW IT STRAIGHT! With this simple trio of projector props, your screen image will always be on the level GEORGE MERZ, FACL Photographs by Walter Gray FIG. 1: The three projector props designed and fabricated by the author on display in front of projector. FIG. 2: With two front props in position, note marked difference in elevation between left and right units. PftOJECTOfl CASE REAR FIBRE STEEL PLATE FIG. 3: Diagram makes clear the positioning of front passed through slots cut in base plate of projector. ^L NY movie maker who has ever given a show outside of his own home MJ^ — or even mside it, for that matter — must long since have run m ^ into the problem of leveling his screen image. I know I have in the public screenings I've been giving here in Hollywood, Florida. Either the floor on which you set up your screen is out of true or the projector stand or (worse yet!) the card table provided for your machine has seen sturdier and more level days. In either case, you can't fit a leveled projector image to an unleveled screen — and vice versa. And, although every projector these days has a built-in tilting device, its operation is not the answer to an unlevel screen image. For the projector tilting device simply raises or lowers the entire front of your machine. What's needed is some method (other than matchbooks) of raising or lowering each front corner of the projector independently. The method I have worked out is pictured on this page. It consists of a set of three jacks, which are shown in closeup in Fig. I. Two of them, you will note, are adjustable. These are used one at each front corner of the projector (see Fig. 2), while the third unit is used at the center of the projector's rear edge and does not require adjustment. With these jacks in place, the projector has a three-point bearing and any kind or degree of adjustment becomes possible to align it with your screen. You will note, for example, in Fig. 2 that the jack at left in the picture has been elevated markedly more than the unit at the right. And yet the base line of the projector is clearly level from side to side. This difference in adjustment was arranged purposely for the illustration to suggest how badly out of true an old card table can be as a projector stand! To make these parts, I first fashioned wooden patterns for both the front and rear units. From these, I then had aluminum castings made — two of the front unit, one of the rear. The two thumbscrews ( % of an inch in size) were factory-made, so that it was only necessary now to drill and tap the aluminum brackets to accept them — and then to add on the rounded pads or feet. These latter as illustrated did require a bit of lathe work; but you can easily avoid this by inverting a couple of bottle caps under the thumbscrews (see Fig. 3). The point, of course, is to keep the bottom ends of the screws from marring the table top when they are turned to make, an adjustment. In my use of these three jacks I have not made them a permanent part of the projector. For I have found that it takes only a few seconds to position them in setting up for a show. And in knocking down afterwards I simply lift up the projector slightly and they fall away freely. However, to install them properly on the B&H Showmaster pictured, it was necessary to cut three small rectangular openings through both the steel and fibre sheets which sheath the projector's under surface. These holes (they are scarcely over Vo inch in length) permit the offset members of the brackets to be inserted above the projector's bottom plate, thus bringing the tongue parts of the brackets into firm contact with the projector's sheath (see Fig. 3). As already mentioned (and made clear in the pictures), the three jacks I have designed are dimensioned specifically for use with the Filmo Showmaster projector. It should be simple, however, to adapt this design to machines of other make. And in the meantime, if you have a Showmaster (or a similar B&H projector), you'll find the wooden patterns for these castings on file at League headquarters. I have left them there for other ACL-ers to use as needed. From mv own experience, I feel sure and rear props and how they are ... .. , . , Bottle cap is used as screw shield. you will like using these projector props. FRONT