PHOTOGRAPHY BY ULTRAVIOLET AND INFRARED 



60» 



photoflood or other lamp is used for focusing and composition and is wired into the 

 circuit as shown in the diagram. The following table gives exposure data for (a) 

 the Eastman Infra-red Sensitive plate, the Eastman Clinical Camera (with //7. 7 lens), 

 and the Kodak Recomar "33" (with //4.5 lens); the Wratten No. 87 filter over 

 the lens; photoflood or photoflash lamps in Kodaflectors; development for 5 min. in the 

 Eastman D-19b or the Eastman X-ray developer at full strength at 65°F. (6) the 

 Kodak Retina I and Retina II using Kodak Infra-red Film, Type IR-135; the Wratten 

 No. 87 filter over the lens; photoflood or photoflash lamps in Kodaflectors; develop- 

 ment for 12 to 15 minutes in Kodak fine-grain developer DK-20 at 65°F.; if D-76 

 developer is used, one-half the indicated exposures should be given and the film 

 developed for 10 to 15 min. at 65°F. If the Wratten No. 25 filter is used instead 

 of the No. 87, one-half the exposures indicated may be given. 



Table III. — Exposure Data for Infrared Materials 

 a. Exposure Data for Infrared Photography with Eastman Clinical Camera and 



Kodak Recomar "33" 



If pictures are to be made in total darkness, the Wra'tten No. 87 filter should be used 

 over the light sources, arranged in a holder that will prevent white-light leakage. 

 The Wratten No. 87 filter is specially made for this purpose in sizes 10 by 12 in. and 

 8 by 10 in. in the same form as safe lights. Using two pairs of photoflood lamps in 

 reflectors, and the Eastman Infra-red Sensitive plate, the exposure will be of the 

 order of 1 sec. at //4.5 if the lamp units are about 6 ft. from the subject. The fila- 



