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HANDBOOK OF PHOTOGRAPHY 



T.\BLE III. — Filter Data 



Table IV.— E^|^psTJRB Multiplying Factors for Wratten Filters in 



Normal Daylight 



: (Agfa Anspo Film) 



are most effective for this purpose; for overcoming light haze the filter may be propor- 

 tionately lighter. The use of infrared-sensitive emulsions to penetrate fog is a special 

 application, the film itself in this case discriminating in favor of the longer less-scat- 

 tered wavelengths. 



The combination of infrared emulsions and light-red or orange filters, referred to 

 in Films and Film Characteristics as a means of getting night effects in daylight, 

 requires no marked change in photographic technique, except that it is desirable to 

 eliminate red in settings. To this end one Hollywood studio repainted its "Brown- 

 stone Street" a bluish gray, equally suitable for day shooting and infrared night 



