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Fluorescent lamps

This type of light source falls under the category of electric discharge lamps, as it relies on the same theory as it often contains a drop of mercury that evaporates when the electric current is flowing, but fluorescent lamps have the inner surface of the glass coated with materials whose properties are to emit fluorescence (1). ) when the short-wave ultraviolet radiation resulting from the spectrum of mercury vapor falls on it. The color temperature of the rays emitted from fluorescent lamps depends on the type of material with which the inner surface of the lamp glass is coated. It is possible to make these lamps so that they emit rays whose color matches the rays of daylight (2). These lamps are often used for lighting offices, homes and indoor spaces. It will not be harmful to use it as a source of lighting in black and white photography, but it is not desirable in color photography because it does not belong to the category of light sources with a discontinuous spectrum.

Which is also known as the Line Spectrum (3) and the color temperature of the fluorescent lamps may agree. Those emitted by tungsten lamps and this agreement is visible, but the photographic results when using them in photography differ greatly.

Whereas the conditions of color interior photography in offices or homes may require the use of these light sources by necessity, so we mention below the filters that Kodak and Ensco factories recommend using with their fast-sensitive films in these urgent conditions (1).

The necessary optical filters when color photography is compulsorily in the light of fluorescent lamps with ectachrome films:

Kodak factories recommend that only colored film intended for daylight be used when photographing under fluorescent lamps known as daylight lamps.
Daylight type Fluorescent Lamps
As for color films that were prepared for imaging in tungsten light, they may require almost the same filters, but at the expense of a significant decrease in the speed of the film's sensitivity. The previous recommendations were made assuming that fluorescent lamps were the only light sources.

All previous recommendations are to use the previous filters as a starting point for guiding the photographer, and it is always appropriate to conduct initial experiments before the final shooting in cinematic films to verify their full validity due to the different characteristics of different fluorescent lamps.