Amateur Cine World (May 1934)

Triple Negative HE width of standard film is 35mm., this allowing an image on the film measuring 18mm. by 24mm. The difference between actual width and image width is accounted for by the perforations in the film on either side. Sub-standard films include the 17.5mm. (picture area, 15mm. by 9mm., with perforations on both sides of the film), the 16mm. (picture area, 10.5mm. by 7.62mm., with perforations on both sides of the film), the 9.5mm. (picture area, 6.5mm. by 8.5mm., with perforations in the centre of the film) and 8mm. (picture area, 5mm. by 3mm. with a perforation on one side of the film only). The 9.5mm. size of film, perhaps, provides the most interesting material for an account of how standard size films are reduced to substandard for showing in the home. The process is not intricate but it does necessitate great care in operation. From the standard size negative a positive copy is printed by contact. This is similar to the prints used in the picture theatres but is not exactly like them. There are two How Your 9.5 mm. REDUCTION PRINTS Are Made points of difference, these being the printing of the positive on special stock known as “ duplicating ’’ and possessing a very fine grain, and the development of this print in a way that will avoid excessive contrasts and bring out all the half-tones, shades and minute details to be found in the original negative. This type of print, which is too soft for ordinary theatre projection purposes, is called a ‘‘ dupe positive.” Optically Printed From the soft 35mm. print a reduced picture is optically printed; that is to say, the image on the soft print is thrown on to the film to be printed so that it is reduced to the required size—in this case, 9.5mm. This process is similar to that used in ordinary photographic work for enlarging, but reversed in practice. A special high grade lens is used in order that none of the image on the soft print is lost or distorted. Further still, the source of light for printing is adjusted according to the density of the ‘ dupe positive.” In printing from a positive a reduced negative is obtained—but it is not on 9.5mm. stock. The reduction prints are made on 35mm. stock with a special narrow perforation on either side and in rows of three. This effect is obtained either by using a prismatic 9.5 mm. film after splitting, notching and perforating. attachment, dividing the original picture into three distinct images, or by passing the film through the printer three times. A triple negative is thus obtained and from this any number of triple positives can be printed by straightforward contact. With this process accomplished, the triple positive needs perforating, notching and finally slitting to make three 9.5mm. copies. The notching is done by a machine cutting three notches at a time, the placing of the notches being controlled by the “ frame” desired to be held stationary before the lamp of the projector when the film is projected ; particularly does this apply to titles. With the film perforated in the centre and notched according to requirements, slitting forms the last operation. The triple positive is cut into five sections by circular knives driven at high speed. Three of the sections are the familiar 9.5mm prints and the other two consist of the side perforations of the 35mm. film rendered useless since the film is now driven by central perforations. After each operation, and finally, the films are tested. HOW “AMATEUR CINE WORLD” WILL HELP YOU TO GET THE MOST OUT OF YOUR HOBBY Free Services for Every Reader Readers of Amateur Cine World are entitled to use the following services free. All that we ask you to do when making use of them is to send the coupon you will find on page iii of cover. TECHNICAL ADVICE on any phase or aspect of amateur cinematography. Replies to questions of general interest will be published in these columns. In the case of queries concerning some mechanical trouble with your camera, projector or other apparatus it is often difficult to diagnose just where the fault lies. In many cases, therefore, it would be a waste of time sending a letter about it. We invite you instead to send the apparatus itself to us. But if you think that a letter will explain your difficulty sufficiently, then write to us. If you decide, on the other hand, to send us the camera or whatever it may be, with a brief covering note as to what the trouble is, please remember to include the cost of the return postage. We will then get the apparatus overhauled and advise you as to what is necessary to put it in first rate working order. If, however, we find the fault to be of some magnitude that will necessitate the apparatus being returned to the manufacturers, we ourselves will forward it to them and will advise you what their charge, if any, will be. But you may feel disinclined to have the apparatus repaired as we suggest. Well, you are under no obligation whatever. Just advise us and we will see that the article is returned to you. ‘REVIEW OF FILMS. Each month we shall publish reviews of reader’s films. “By reading the criticism of other people’s films you will get useful ideas for your own. Equally, the publication of a notice of one of your films by a professional critic helps other people. We are going to give the same serious attention to the review of amateur gee as the daily Press gives to professional ms. To the makers of those films which show evidence of good idea and technique and provide an affirmative answer to the question : “Is it reasonably good entertainment?” we shall present a free leader titled: ‘‘ Passed by the Board of ‘ Amateur Cine World.’”’ This will convey that the film reaches an accepted standard of merit. Any type of film—family, scenic, featurette —is eligible for the award and it may be of any size. Readers who send their films for review should state if these are available for exchange with other readers. A note will then be inserted to this effect. REVIEW OF AMATEUR FILM PLAYS. Amateur film plays are invited for review and will receive the same careful attention as ‘‘personal” films by individual workers. 45 For meritorious productions a free leader will be given titled: ‘‘ Examined by the Board of ‘Amateur Cine World’ and Specially Commended” will be given. The reasons guiding us in making the award are given in full on page 25 of last month’s Amateur Cine World. The number of awards given to societies and _ individual workers will be recorded in Amateur Cine World each month. . Societies sending films for review should state if these are available for hire by other clubs. A note will then be inserted to this effect. TWO HANDSOME FREE GIFTS FOR READERS. Every reader who subscribes to Amateur Cine World for twelve months will receive free an attractive animated leader and a presentation copy of “ Practical Home Movies,’’ by The Cineman, the latest and most up-to-date book on amateur cinematography yet. published. A year’s subscription costs 7/6 post free. Send your postal order, money order or cheque (which should be made out to Amateur Cine World) to the Subscription Dept.. AMATEUR CINE WORLD, Link House, 4-7, Greville Street, London, E.C.1. Do not forget to say what size of film leader you require—i.e., whether 9.5mm. or 16mm. There are other services as well. For full list see last month’s issue.