التصوير الملون نهارا ضد مصدر الضوء .. كتاب الإضاءة والفلم

Color photography during the day against a light source:

No problems will arise for the photographer if the lighting is front lighting, i.e. if the light source is facing the subject to be photographed, but if the lighting is side lighting or back lighting, then the matter is to use reflectors or light diffusers (Fig. 11) to calm the intensity. The contrast in illumination resulting from the large intensity of illumination of parts facing the source of light from those far from it (1). It may also be very useful to use a flash light (2) to illuminate the shadow areas in the subject, provided that the color temperature of the flash light rays agrees with the color temperature of the daylight rays.

Despite the usual warnings from color film makers to avoid color photography against the light source (against the light) or (contre jour), there is no doubt that we have all seen many images recorded against the light source (silhuettes) on color films, and we have seen in them striking aesthetic values. Therefore, we do not find a reason to always adhere to the established rules, as artistic creation sometimes calls for liberation from restrictions and rules. However, I recommend choosing the appropriate light conditions in which the light is diffused (from clouds, for example) in order to reduce the strong contrast between the high light areas and the shadows areas, and as examples of scenes that can be photographed against the light source when the light is distributed: trees, gardens, and the luster of water , people...etc. In such cases, the appropriate exposure is estimated based on the intensity of the brightness of the High Lights areas, regardless of what the exposure scale dictates if we direct it towards the shadows areas. In this case, we will find that the details have disappeared to a large extent in the areas of shadows, while the areas of high light will appear as white lines on the edges of the objects.

It is also permissible to estimate the exposure according to what suits the areas of shadows, despite photographing against the light source. Here, we find that the details of the shadows appear more clear, while the high-light areas appear in the form of splashes of light with no details at all, and their colors are very desaturated-tinted.

Electric industrial light sources used in photography:

When is it necessary to use artificial light sources in photography?

1- When natural light is not available at all.

2- When the natural light falls on the subject being photographed from a direction that does not suit the desires of the photographer, such as the daylight source being behind in relation to the object to be photographed, and thus casting strong shadows from the opposite side of the natural light source, and here the matter requires the use of artificial light sources to illuminate shadow areas. In view of the possibility of different color temperatures of the artificial light sources from the natural light source, therefore, in the matter of color photography, we must work on unifying the color temperature of the rays that reach the film from the two sources, so that it is consistent with the color temperature for which the film was prepared (1).

3- When there is a strong contrast in the brightness of parts of the same subject, such as the case of photographing in bright sunlight, where strong shadows are cast below the prominent parts. Here, the degree of luminance contrast increases, which calls for the use of any artificial sources that may sometimes be a flash light). It is also possible to use light reflectors sometimes (Fig. 11 p. 38) without the need for artificial lighting.

In the following pages, we will talk about the industrial electric light sources used in photography, which we have already mentioned on page 29 of this book, with the exception of electronic flash tubes, which we will not refer to in this book, since we have previously talked about flash light photography. Detailed in the camera book (2).