International projectionist (Jan-Dec 1954)

PROJECTION IN EUROPE (Continued from page 13) trim at 50 amps. 109% when the Wabenkondensor is used. In addition to providing screen illumination which is uniform in brightness and color, therefore, the Wabenkondensor actually increases the brightness of the picture! Helps In Small Theatres The very small theatres which are so numerous in Europe find in the Wabenkondensor a perfect solution to their lighting problems. Beck (HI) arcs consuming less than 35 amps. are not ordinarily feasible because of their extreme "hot-spot" characteristics and discolored light. Now, the Wabenkondensor permits the use of Beck arcs drawing as little as 25 amperes because it insures screen light which is perfectly uniform both in brightness and color. This is one of the "selling points" of the Wabenkondensor, though the writer must admit that he is not able to vizualize a theatre screen so diminutive as to be excessively bright with a 35 or 40amp. Beck arc. It is always a good thing to have plenty of light to spare; Wide Screen Projection Requires More Light... Get an "HS" T^BS^HS RE©. U.S. PAT. OFF. The "HSD" dual-ballast rheostat available in two capacities — 65-100 amperes and 5-5} volts; 851 15 amperes and 5-25 volts. The "HS" Tronsverter 115/230 amperes Control Panel Type G to Meet THIS INCREASED POWER REQUIREMENT • Exhibitors everywhere are finding out that wide screen equipment requires increased amperage for proper screen illumination. Loss of light through use of filters plus giant screen sizes makes existing projection equipment inadequate to do the job. Additional power is a must, for carbon-arc amperage and voltage requirements have been increased up to 100% for wide screen projection. In order to get this increased power, get a Hertner "HS" Transverter. When you buy a Transverter you are obtaining a power conversion unit that has been the standard of the industry for nearly half a century. Distributed by National Theatre Supply In Canada: General Theatre Supply Company THE HERTNER ELECTRIC COMPANY 12690 ELMWOOD AVENUE . . .CLEVELAND 11, OHIO A General Precision Equipment Corporation Subsidiary and when there really is far too much light, a contrast-enhancing gray screen may be used. The Wabenkondensor is intended for HI lamps only, and may be used MOTORS MOTOR GENERATORS GENERATOR SETS FIG. 8. The Ernemann X modified for undistorted projecHon at a 22° tilt. This projector was first built to order for the Eldgenossische Technische Hochschule, Zurich, Switzerland, where it is now giving satisfactory performance in the new physics lecture room. with arcs of any power up to 50 or 60 amps, before the danger of cracking the lens-array plates becomes really great. The projectionist who is lucky enough to have the Wabenkondensor as a component of his lamp equipment can forget his mirror and carbon adjustments — almost. The light remains unform in brightness and color even when the crater burns at quite a slant, though it is hardly necessary to add that for the brightest light it is still necessary to maintain a crater formation sufficiently good to prevent the glowing gas ball from streaming off in the tail-flame of the arc. But most startling of all is the fact that the amount, uniformity, and color of the screen illumination with the Wabenkondensor remains practically constant when the arc is moved to and from the mirror through a considerable range. In addition to the regular Ernemann Model X projector, there is a 2S INTERNATIONAL PROJECTIONIST • JANUARY 1954