كيف يتحقق الإحساس بالعمق الفراغي في الصورة رغم أنها لا تتميز إلا ببعدين فقط .

How is the sense of spatial depth achieved in the image, even though it is characterized by only two dimensions?

The photographer usually hopes that the photographic image honestly expresses the reality of the visuals that he perceives when he looks with his eyes at a specific subject, including the sense of spatial depth (i.e. the third dimension), despite what we know about the photographic image that it is nothing more than flat. It is characterized by only two dimensions, length and width, so what are the ways to achieve these hopes? In order to answer the foregoing, we must first understand those visual indications that lead to the individual's sense of spatial depth when looking at different subjects in nature, and then we look at the availability of these indications in the photographs that we record for these subjects. We will divide these visual cues into two parts as follows:

(a) Indications that lead to a sense of depth when looking with one eye:

It is the case that is similar to the usual optical imaging.

We summarize these indications as follows:

1- The ratio between real and apparent volumes and lengths.

2 - Contrast between shadows and light areas (i.e. high lighting)

3- The lens of the eye adapts according to the distance of the body from it.

4- Decreased depth of field as an effective factor in increasing the sense of the third dimension.

5- Covering parts of distant objects because others are located in front of them and are closer to the eye.

6- The center of vision has changed.

7- Pneumatic perspective.

8- The position of the objects in relation to the horizon line.

(b) Indications associated with the state of looking with both eyes:

It is the case similar to stereoscopic imaging:

1- Convergence of lines of sight.

2- The slight difference between the two images that the eye receives.