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التصوير الفوتوغرافي الحديث
تجهم الصور ..
تأثيرات العدسة بسبب وضع الكاميرا ..
وجهة نظر ..
LENS EFFECTS DUE TO CAMERA PLACEMENT
PERSPECTIVE
Perspective is determined by the point of view from which a photograph is taken . Abrupt perspective , which in extreme cases may be called distortion , is caused by using too near a viewpoint . If the lens is placed very close to the subject in making a portrait , the perspective may be rather violent and even grotesque .
It is very important to understand clearly that abrupt and exaggerated perspective is not caused by using a short - focus lens , but by having the camera too close to the subject . This is shown clearly in Figure 19 , which is a diagrammatic view of a camera set up to take a close - up portrait . The distance between the camera lens and the subject's nose is 12 inches . The distance between the lens and the subject's ear is 18 inches . You know , of course , that the closer the subject , the larger the image . Translating this into specific figures , the subject's nose will photograph 1½ times as large as it should in relation to the ears , which is certainly a false and grotesque portrait .
Now moving the camera back 6 feet ( 72 inches ) the ratio of the nose to the ears is 84 to 90. This gives us a perfectly natural perspective . Figure 20 illustrates an example of exaggerated perspective caused by holding the camera too close to the subject . Note the exaggerated large foot .
Fig . 19 Why holding camera too close to subject produces an unnatural picture . Nose at 12 inches from camera would be 1½ times its natural size as compared with ears .
Fig . 20 Exaggeration resulting from shooting too close to subject .
Since the short - focus lens is not responsible for perspective distortion , why has it been so frequently blamed ? The answer lies in the fact that short - focus lenses produce smaller images . Since the natural tendency of most photographers is to fill the frame with the subject , the camera frequently is brought too close to the subject . The real reason for the extreme perspective is the closeness to the subject , not the short focal length of the lens . When using a lens with a long focal length , you must back away from the subject . in order to get it all in . Because of this , longer focal length lenses produce more natural perspective . They compel the photographer to keep a reasonable distance from the subject .
If you have the equipment to do your own enlarging , the safest way to do portrait work with a short - focus lens is to shoot from a correct distance , then enlarge part of the negative . This will give you a close - up photograph with natural perspective . With color slides and movies , of course , this is not practical . That is why the color slide or motion picture photographer must have a much wider assortment of lenses than the photographer who works exclusively in black and white .
A violent perspective is not necessarily wrong . It may sometimes be used for its dramatic effect or special element of humor . For example , a commercial photographer may want to give great emphasis to a figure in the foreground . He can do so by using a short - focus lens and getting quite close to his subject to give it greater size and , thereby , increase its importance .
Some very amusing pictures can be taken by using a short - focus lens very close to the subject as when photographing a fisherman showing off a prize catch . If the fisherman holds the fishing rod in front of him so that the fish is very near the lens , it is possible for the photographer to secure a picture that would satisfy the most ambitious fisherman , for in this way the fish could be made to appear five or six feet long .
The experienced photographer selects the lens which gives him the best perspective for the specific job he wants to do . If he wants the foreground subject to appear much larger and more dramatic with respect to the background , he uses a short focal length lens , such as a wide angle lens , and gets in close to his subject . This will make the subject appear much larger in relation to the background , thus giving it greater emphasis . On the other hand , if he wants the background to dominate , he gets farther back from his foreground subject and uses a longer focal length lens to bring the foreground subject down to a more . appropriate size .
In Figures 21 , 22 , and 23 , we show that it is the position of the camera rather than the focal length which determines perspective . Figure 21 is exactly the same as Figure 11 , and it was taken with a 35mm lens . Figure 22 is the same as Figure 13 and this , you will recall , was taken with an 85mm lens . Figure 23 is actually the central area of Figure 21 enlarged to give the same image size as Figure 22. You will note that the perspective of both Figures 22 and 23 are identical , even though one was taken with a 35mm lens and the other with an 85mm lens . Since both photographs were made from the same camera position , we see that it is the camera position which determines perspective , not the focal length of lens . This subject will be discussed again in more detail in later assignments when we deal with the actual business of making pictures .
Fig . 21 This photograph was taken . with a 35mm lens . It is exactly the same as Fig . 11 .
Fig . 22 This photograph was taken . from the same spot as Fig . 21 , except that an 85mm lens was used .
Fig . 23 This illustration is actually the central portion of Fig . 21 enlarged to the same image size as Fig . 22. As you can see , the perspective in Fig . 22 and Fig . 23 is identical even tho one was taken with a 35mm lens and one was taken with an 85mm lens .
تجهم الصور ..
تأثيرات العدسة بسبب وضع الكاميرا ..
وجهة نظر ..
LENS EFFECTS DUE TO CAMERA PLACEMENT
PERSPECTIVE
Perspective is determined by the point of view from which a photograph is taken . Abrupt perspective , which in extreme cases may be called distortion , is caused by using too near a viewpoint . If the lens is placed very close to the subject in making a portrait , the perspective may be rather violent and even grotesque .
It is very important to understand clearly that abrupt and exaggerated perspective is not caused by using a short - focus lens , but by having the camera too close to the subject . This is shown clearly in Figure 19 , which is a diagrammatic view of a camera set up to take a close - up portrait . The distance between the camera lens and the subject's nose is 12 inches . The distance between the lens and the subject's ear is 18 inches . You know , of course , that the closer the subject , the larger the image . Translating this into specific figures , the subject's nose will photograph 1½ times as large as it should in relation to the ears , which is certainly a false and grotesque portrait .
Now moving the camera back 6 feet ( 72 inches ) the ratio of the nose to the ears is 84 to 90. This gives us a perfectly natural perspective . Figure 20 illustrates an example of exaggerated perspective caused by holding the camera too close to the subject . Note the exaggerated large foot .
Fig . 19 Why holding camera too close to subject produces an unnatural picture . Nose at 12 inches from camera would be 1½ times its natural size as compared with ears .
Fig . 20 Exaggeration resulting from shooting too close to subject .
Since the short - focus lens is not responsible for perspective distortion , why has it been so frequently blamed ? The answer lies in the fact that short - focus lenses produce smaller images . Since the natural tendency of most photographers is to fill the frame with the subject , the camera frequently is brought too close to the subject . The real reason for the extreme perspective is the closeness to the subject , not the short focal length of the lens . When using a lens with a long focal length , you must back away from the subject . in order to get it all in . Because of this , longer focal length lenses produce more natural perspective . They compel the photographer to keep a reasonable distance from the subject .
If you have the equipment to do your own enlarging , the safest way to do portrait work with a short - focus lens is to shoot from a correct distance , then enlarge part of the negative . This will give you a close - up photograph with natural perspective . With color slides and movies , of course , this is not practical . That is why the color slide or motion picture photographer must have a much wider assortment of lenses than the photographer who works exclusively in black and white .
A violent perspective is not necessarily wrong . It may sometimes be used for its dramatic effect or special element of humor . For example , a commercial photographer may want to give great emphasis to a figure in the foreground . He can do so by using a short - focus lens and getting quite close to his subject to give it greater size and , thereby , increase its importance .
Some very amusing pictures can be taken by using a short - focus lens very close to the subject as when photographing a fisherman showing off a prize catch . If the fisherman holds the fishing rod in front of him so that the fish is very near the lens , it is possible for the photographer to secure a picture that would satisfy the most ambitious fisherman , for in this way the fish could be made to appear five or six feet long .
The experienced photographer selects the lens which gives him the best perspective for the specific job he wants to do . If he wants the foreground subject to appear much larger and more dramatic with respect to the background , he uses a short focal length lens , such as a wide angle lens , and gets in close to his subject . This will make the subject appear much larger in relation to the background , thus giving it greater emphasis . On the other hand , if he wants the background to dominate , he gets farther back from his foreground subject and uses a longer focal length lens to bring the foreground subject down to a more . appropriate size .
In Figures 21 , 22 , and 23 , we show that it is the position of the camera rather than the focal length which determines perspective . Figure 21 is exactly the same as Figure 11 , and it was taken with a 35mm lens . Figure 22 is the same as Figure 13 and this , you will recall , was taken with an 85mm lens . Figure 23 is actually the central area of Figure 21 enlarged to give the same image size as Figure 22. You will note that the perspective of both Figures 22 and 23 are identical , even though one was taken with a 35mm lens and the other with an 85mm lens . Since both photographs were made from the same camera position , we see that it is the camera position which determines perspective , not the focal length of lens . This subject will be discussed again in more detail in later assignments when we deal with the actual business of making pictures .
Fig . 21 This photograph was taken . with a 35mm lens . It is exactly the same as Fig . 11 .
Fig . 22 This photograph was taken . from the same spot as Fig . 21 , except that an 85mm lens was used .
Fig . 23 This illustration is actually the central portion of Fig . 21 enlarged to the same image size as Fig . 22. As you can see , the perspective in Fig . 22 and Fig . 23 is identical even tho one was taken with a 35mm lens and one was taken with an 85mm lens .
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