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PHOTOGRAPHIC RECORDS Both a 16 mm motion picture camera and a motor driven, 35 nnn, single lens, reflex camera provided time-lapse coverage of expected areas of distress during the tests. The motion picture camera was a Bolex H-I6 Rex h with an 86 EE Vario Switar lens. This reflex viewing camera had a film capacity of 100 f t . The 35 mm time-lapse photos were ob- tained with a 35 mm lens. Film capacity of the Nikon F was 250 exposures. A Samenco Intervalometer was used to control time interval between exposures. At the beginning of the tests, the cameras oper- ated at speeds of 6 frames per minute. Speed was increased to 30 frames per minute when failure appeared imminent. The csuneras oper- ated only during the times loads were being applied. Composite photographs of the underside of the roof area in each test were made with a Nikon F 35 â¢n camera using a 50 mm lens. The camera was motor driven and had a capacity of 36 frames. Timber guide r a i l s made from 2 x 4 -in. lumber were set between the anchor bolts in each test. This arrajigement i s seen in the lower portion of Fig. 20. The camera was mounted lens upward on a movable dolly. A flash unit was mounted on the dolly adjacent to the camera. The dolly guided by the r a i l was pulled across the test area with a rope pulley system. The camera was triggered aJid pulled along the guide r a i l from outside the test area. This system was devised so that pictures could be taken during a test. At predetermined intervals, the dolly was stopped and a photograph was taken. Five to six exposures were made along a 30-ft panel length. The camera was run along a l l of the r a i l s to cover a test area. Each exposure covered an area approximately T-ft wide and 10-ft long. This provided sufficient overlap so that the individ- ual pictures could be matched to form a composite of an entire test area. 2-13
Conrposites were made before, during, and after each test. Before and after each test, cracks were marked on the f l a t black celling with white chalk. Fig. 21 shows a composite of Test I I I and a single frame from this composite. Composites of each of the three test areas before and after failure are shown in Reference 1. Condition of the structvire before and after each test was recorded with a Hasselblad ^0 C camera and a Leica M3 camera. The Hasselblad ^ 0 C i s a single lens reflex camera using 120 film. The Leica M3 i s a range- finder camera using 35 film. Frames from the single lens reflex ca- mera were 2.25 x 2.25 in. A l l columns and wall areas were photographed before and sifter each test. Detailed photographs were taken of failure areas after each test. Both motion picture and s t i l l cameras were used for general coverage of the tests. Photos were taken of test preparation, test equipment, and test arrangements. Post-test investigations were also covered. 2-14
