The Moving Picture World (April 1907)

84 THE MOVING PICTURE WORLD. A correspondent asks the following question: "Is the Urban Motion Picture Camera, Model D, an infringe- ment on the Edison patent? This camera is made by the Urban Trading Company of London." Another asks: "What camera can I use that does not infringe the Edison patent?" A third says: "I am an amateur and have a War- wich Camera, with which I obtained a large amount of pleasure last summer, cinematographing pleasure, hunts, yachting and other parties, for my own amusement, not for profit or gain. I obtained my film for exposure, and got same developed by Mr. . Now what position am I in, and how does it affect Mr. if I take more subjects? Must I get another camera, or can I use the one I have, and under what terms or restrictions? Any information you can give me will be esteemed." The above queries are selected from a number of simi- lar character we are receiving at this office, and while we do not want to harp upon one string too much, we consider them of such importance to warrant us giving special note to them. At the same time we urge our readers to study the decision as published in our issue of March i6, and draw their own conclusions therefrom; and, if they wish, give us their opinions. Our columns are open to them, and we invite full and free discussion of the pros and cons. In reply to Query I., we are of the opinion that the Urban Camera, Model "D", does infringe the Edison, because, while it is superior to the Warwick, it works on much the same principle. Query II., is a hard nut to crack. We have mentioned this before, and asked our readers* assistance in this mat- ter; but, at the time of writing, no light has come. We believe the Gaumont and Lumiere Cameras do not in- fringe the Edison patents, but will quote from the deci- sion : "The film, as it comes from the delivery roll, has a row of holes along each edge; when it is in the -film- slide these holes are engaged by means of a reciprocating two-tined fork, carrying small studs or pins which pass into the holes on the opposite edges of the Him, in the same way as the sprockets pass into the holes in com- plainant's machine. As these studs or pins are inserted on the down stroke of the fork and withdrawn on the up stroke, the film is intermittently fed across the field of the lens. ... But the 'intermediate section' is moved across the lens fust by the interlocking engagement be- tween tht sprocket or pin and a hole in the film, thereby moving it positively, regularly, evenly and very rapidly without jarring, jerking or slipping — the parts being ar- ranged so that the movement shall be intermittent. In our opinion the bifurcated fork with studs is the fair equivalent of the wheel with sprockets/' From the above it will be plainly seen that any camera with a continuously moving film, without a pause or inter- mittent motion, in the exposure of the same, is the cam- era or cameras that do not infringe the Edison patent. Again we ask, have any of our readers a camera, or do they know of such, that complies with this? If soj will they be kind enough to send us the requisite information? Our amateur friend's query is a pertinent one. We believe we are right in saying, that for his own pleasure he stands in the same position as he did before the deci- sion, and so long as he does not trade or barter his films, or negatives, he need have no fear, but go on the even tenor of his way. At the same time he will gain in the end if he waits a little, pending the publication of Mr. Edison's views; or at any rate, write to the firm for their opinion. The present. juncture in animated photography has stimulated the inventive faculties of mechanics to over- come the seeming deadlock, or halt, in the march of progress, which for the moment is a stumbling block soon to be swept away and added vigor will be given to the trade of the future. In furtherance of this aim, we were informed by one manufacturer that he had a camera well in hand that is absolutely unique in its con- ception and working parts, entirely different to anything yet put on the market. A friend of the writer's is also making progress with a model, which we saw fully dem- onstrated, and which overcomes all the difficulties ex- istent in cameras at present in use, both in the simplicity of its construction and the rapidity of its work. There may be others working on the same lines, all endeavoring to pull out the wedge that is scotching the cogwheels of a great and growing industry. The cause of evolution and survival of the fittest will never stand still, and if a rock dams the river at its source another outlet is always made. The Optics of Photographic and Projecting Lenses. Chapter I. A FEW POINTS ON LENSES. If Several questions that have reached us lead us to be- lieve that no matter how well the average person may be posted on other subjects, a general ignorance prevails regarding the construction and use of lenses and the laws of optics. We therefore publish a series of articles on this subject, covering all requirements of photo-optics, with a special chapter on the use of projection lenses and condensers. J The old-fashioned "rule of thumb" opticians may have imagined that they were the po ss essors of some super-