Early BW films were mostly sensitive to the blue and green side of the spectrum. Only later did they become more sensitive to the entire visible spectrum (including the red zone, which we consider warmer). They were called panchromatic films (as opposed to earlier orthochromatic films).
Early BW films were mostly sensitive to the blue and green side of the spectrum. Only later did they become more sensitive to the entire visible spectrum (including the red zone, which we consider warmer). They were called panchromatic films (as opposed to earlier orthochromatic films).