قياس الأشعة المنعكسة ٢-a .. كتاب آلة التصوير

In order for these areas to appear white in the image, and the shadows to appear black: either or standing gray (Figs. 190-192-193). This method is known as Hith Light Reading.

It is self-evident that the reference for following the method that we have shown in item (fourth) or in item (fifth) is the desire of the photographer himself, which is controlled by the emotional, dramatic effect that he wants to paint the image with.

Sixth: a close-up measurement of the main subject’s luminous intensity:

When there is a difference between the brightness of the main subject in the image and the intensity of the brightness of the surrounding medium, the appropriate exposure is estimated for the brightness of the main subject. Thus, the photographer has to first decide the most important parts of the scene, i.e. the part that he wants to pay the first attention to, and then approach it and direct the meter towards it so that the angle of acceptance of the meter is not inclusive of any other subject, then he estimates the correct exposure that matches the intensity of its illumination, regardless of what There are other topics around it that are considered secondary and fall in the second place of importance. In fact, it would not hurt that these secondary topics come out having been overexposed or underexposed beyond the correct limit, as this is what gives the image an aesthetic value, as the main topic attracts the attention of the eye at first sight. With nothing but him due to the correct exposure he received. Just as it is possible that the intensity of the main subject’s illumination decreases in relation to what surrounds it, as if we photographed a brown face with a bright sky behind it (Fig. 195, p.

The intensity of illumination of some parts of the image may be much greater than the intensity of illumination of the main subject, and the intensity of illumination of other parts is much less than the intensity of illumination of the main subject at the same time (Fig. 196).

Seventh: Measurement of the rays reflected from the back of the image without the frontal subjects:

In the case of photographing objects against a light source, this method follows the desire of the photographer to make these foreground objects appear completely black in the image, while what is behind them (the most luminous) appears either completely white or gradient in color, and this is the photography method known as Silhouette (Fig. 194). ..

In this case, the exposure factor is estimated according to the intensity of the background illumination of the highly illuminated image, without giving any consideration to the foreground objects that must be underexposed to the maximum so that they appear completely transparent in the negative. If the sky or clouds are at the back of the image, the exposure meter should be directed towards it directly, and the exposure should be estimated according to the intensity of its illumination.

The following is noted in such pictures:

(a) No direct light rays from the light source (which is the sun) fall on the lens. Rather, the front body must be a barrier between the lens and the direct rays.

(b) It is very good for the body to be fully lateral so that the edges of the body are clear and distinct from it completely.

(C) The appearance of any other obstacle directly behind the body (such as the appearance of a tree or buildings) should be avoided, otherwise the image of the main subject will be mixed with the image of what is behind it, thus its artistic value will decrease, or it will be difficult to identify the main subject.