Projection engineering (Jan-Dec 1931)

Page 18 PROJECTION ENGINEERING News for home movie makers THE introduction of Cine-Kodak supersensitive panchromatic safety film is news to the world of home movie making. This remarkable new film puts an entirely new aspect on the subject of personal movies. The extreme speed and high degree of color sensitivity of supersensitive film batters down many of the photographic barriers of the past. Motion pictures can now be made of subjects that heretofore could not be photographed satisfactorily. Pronounced sensitivity at the red end of the spectrum makes the emulsion of this film particularly efficient when exposed to rays of artificial light — especially light of incandescent lamps. As a result, the range of cine activities is signally extended. With supersensitive panchromatic film, it is now possible — in fact, easy — for amateurs to photograph subjects indoors by the light of ordinary electric lights. No longer is it necessary to use expensive lighting equipment to obtain indoor movies. To say the least, the imagination is taxed in attempting to conceive of all the numerous new channels of interesting movie making that are now open. As a striking example, a living-room can be quickly transformed into a temporary studio simply by placing two or more 100-watt bulbs in as many reading lamps. With the lens set at f. 1.9, one is all ready for first-rate home movie portraits ; closeups of the children, or numerous interesting subjects that do not require the source of illumination to be more than a few feet away. Lighting effects that are different — and beautiful — can easily be obtained by placing additional lights at the sides of and behind the subject. One lighted bridge lamp set behind the subject produces a "back lighting" which gives a pleasing depth and roundness to the picture. See Fig. 1. It should be understood that the direct rays of artificial lights should not be allowed to enter the lens. Lighted floor lamps and table lamps can be included in the picture, and will not cause fog or halation if the bulbs do not show through or under the shades. It must be remembered, however, that brilliant pictures can only be Supersensitive panchromatic safety film for 16 mm. cameras announced. made when there are additional lights (out of range of the camera) for direct illumination. By increasing the number of electric bulbs, the camera can be placed farther from the subject thereby increasing the scope of the picture. An exposure table for Cine-Kodak supersensitive Panchromatic film when it is exposed under artificial light conditions is given: EXPOSURES TABLE FOR CINE-KODAK SUPER-SENSITIVE PANCHROMATIC FILM These exposures are for the CineKodak operated at normal speed. Halve the illumination at half-speed. Distance Total from Lamps Diaphragm Wattage to Subject Opening of Lamps 2 feet f.1.9 200 2 '•< f.2.8 300 2 " f.3.5 400 3 " f.1.9 300 3 " f.2.8 450 3 " f.3.5 600 5 " f.1.9 600 7 " f.1.9 800 9 " f.1.9 1200 Best lighting is obtained by arranging the lamps on each side of the camera, so that both sides of the subject are Fig. 1. In this picture the diaphragm opening was f.1.9, and six 100-watt bulbs were supplemented with two 60-watt bulbs placed in a reading lamp. illuminated. It is advisable to place the lights at different distances from the subject. For example, the table gives an exposure with the lamps 3 feet from the subject ; the lamps can be placed 2^2 and 3^2 feet from the subject. The camera must be in a position so that the lights used for direct illumination will not show in the finder. One of the largest fields of picture activities opened by the new "pan" film is that of indoor sports — basketball games played in well lighted gymnasiums, indoor track events. Other athletic events taking place on well lighted platforms tan be easily photographed when stop f.1.9 is used. If the illumination is exceptionally good, even smaller lens openings can be employed. The increased range of picture taking provided by the new film actually embraces night scenes on brilliantly lighted streets, or theatre districts in large cities. For pictures of this kind the camera must be fitted with an f.1.9 lens and the largest stop (f.1.9) must be used. Best results will be obtained after a rain. The glazed surfaces of the street and the sidewalks will then reflect Fig. 2. In well lighted indoor courts, excellent pictures can be made on supersensitive panchromatic film with the lens opening of f.1.9. the rays of the hundreds of lights, giving added illumination and unusual effects. If the lights are very brilliant, the camera can be used at normal speed. Half-speed gives twice the exposure and generally produces more brilliant pictures. It should be kept in mind, however, that the action of moving vehicles and people walking on the sidewalks will be twice as fast. That is not so objectionable in the case of automobiles or street cars, because they then only appear to move more rapidly, but the action of people walking will be jerky. Fireworks, flood-lighted buildings, camp fire scenes, are all now within the scope of night movie making. The remarkable qualities of the new film are valuable for daylight photography as well as for pictures at night. The increased light-sensitivity of the film is not confined altogether to the red end of the spectrum. It is nearly twice as fast to blue and ultra-violet light as regular panchromatic film, permitting successful pictures to be made under very adverse weather conditions. Unique shots can be made during a downpour of rain with supersensitive film, and the cine camera becomes an efficient instrument during the early hours of the morning or in the weak light of the afternoon.