The simple truth is that photography relies on our ability to successfully portray 3 dimensions within the four borders of our 2 dimensional photograph. It's the ability to construct this 3D illusion that draws viewers into pictures and compels them to explore the photographer's artistic message.
There are several perspective control tools used by photographers (and traditional artists) to establish the illusion of a 3rd dimension. Learning when and how to use these controls provides photographers a powerful technique for directing viewers' attention and interest. Basic perspective controls will be covered in this part of the Primer.
Depth of Field (Selective Focus)
We have discussed the mechanics of controlling depth of field in several sections of this Primer. Depth of field is always present and always impacts the eye's sensation of perspective. Mastering depth of field allows photographers to "selectively focus" on the subject, create depth and de-emphasize other distracting components within the borders of the image.
Our eye/brain has been taught that objects which appear sharp -- as in the image above -- are all probably on the same plane (distance from the eye). At the very least, when the foreground and background are in focus at the same time, our sense of depth becomes confused. When some objects are out of focus while another remains in focus, the sensation of distance is instantly perceived. Our minds say, "These objects can't all be the same distance from the camera because they are not all in focus."
Since the iris of the eye works in the same manner as the aperture of the camera, we have grown up subconsciously understanding and applying the concept of depth of field. The foreground flower above is sharp while the background is out of focus. Our eye instinctively knows that there MUST be distance between the foreground and background flowers. When we selectively use depth of field in our photography, we create and control the illusion of depth or a 3rd dimension.
Linear Perspective
We've all seen linear perspective in action everyday. It is one of the first visual clues our eyes seek when attempting to determine perspective, depth and relative distances within a scene. The picture shown below is a classic example of linear perspective. Although the picture is not fine art, it is immediately recognized as having extreme depth to provide a 3D illusion. The viewer's eye is quickly drawn into this picture. Because our eye/brain combination has been trained to recognize that train tracks are truly parallel, when these known parallel lines begin to converge in a picture, we experience the sensation of depth or a 3rd dimension -- just as we do in the real world.
The converging lines of train tracks and progressively smaller trees provide depth and the illusion of 3D.
The illusion is further enhanced by the trees on either side of the tracks becoming smaller as the eye travels into the picture. Again, our eye/brain knows that in reality trees in a scene are nearly the same size. If these "known" trees become increasingly smaller then distance is assumed, and we have added perspective to create a third dimension -- a sense of depth.
If the tracks had continued parallel to each other (no convergence) and the trees did not become progressively smaller, we would have concluded that all the elements of this picture are on the same plane or distance from the camera.
Linear perspective is also realized when elements of a picture overlap. The eye/brain knows that an overlapping element MUST be in front of the second object. (Two objects can't occupy the same space at the same time.) Consequently, the sensation of depth is immediately recognized. This technique is used frequently by photographers when they place a framing element in their pictures.
Since the iris of the eye works in the same manner as the aperture of the camera, we have grown up subconsciously understanding and applying the concept of depth of field. The foreground flower above is sharp while the background is out of focus. Our eye instinctively knows that there MUST be distance between the foreground and background flowers. When we selectively use depth of field in our photography, we create and control the illusion of depth or a 3rd dimension.
Linear Perspective
We've all seen linear perspective in action everyday. It is one of the first visual clues our eyes seek when attempting to determine perspective, depth and relative distances within a scene. The picture shown below is a classic example of linear perspective. Although the picture is not fine art, it is immediately recognized as having extreme depth to provide a 3D illusion. The viewer's eye is quickly drawn into this picture. Because our eye/brain combination has been trained to recognize that train tracks are truly parallel, when these known parallel lines begin to converge in a picture, we experience the sensation of depth or a 3rd dimension -- just as we do in the real world.
The converging lines of train tracks and progressively smaller trees provide depth and the illusion of 3D.
The illusion is further enhanced by the trees on either side of the tracks becoming smaller as the eye travels into the picture. Again, our eye/brain knows that in reality trees in a scene are nearly the same size. If these "known" trees become increasingly smaller then distance is assumed, and we have added perspective to create a third dimension -- a sense of depth.
If the tracks had continued parallel to each other (no convergence) and the trees did not become progressively smaller, we would have concluded that all the elements of this picture are on the same plane or distance from the camera.
Linear perspective is also realized when elements of a picture overlap. The eye/brain knows that an overlapping element MUST be in front of the second object. (Two objects can't occupy the same space at the same time.) Consequently, the sensation of depth is immediately recognized. This technique is used frequently by photographers when they place a framing element in their pictures.
In the picture above, two concrete posts are used as "framing" elements at the edge of the image. Although the posts and the house are BOTH in focus, our eyes "know" from experience that the posts MUST be in the foreground and separate from the house because the posts overlap the elements behind them. So, in this case, depth of field provided no clue to our eye/brain. Instead it was the overlapping of picture components that created the sensation of depth or 3rd dimension.
Atmospheric Perspective
Why does our eye "know" that the mountain in the picture below is located in the distance and not directly in front of the camera?
Mount Hood, Oregon
There don't appear to be any of the visual cues for perspective that we've discussed to this point. The entire image is sharp, not much overlap of objects and there's very little linear perspective contributed by the trees. Yet we perceive the mountain as being the most distant object in this scene.
This optical phenomenon is called atmospheric perspective. In the real world, there is a subtle tonality difference between near and far away objects. Objects in the distance will appear lighter in tone than if we were standing next to them. In the case of the mountain, the haze in the atmosphere lightens the mountain telling our eyes that it must be farther away than the trees in the bottom half of the picture. In fact, the mountain is about 20 miles away from the camera lens while the foreground trees are about 1,000 feet from the camera. Our eyes have learned this subtle distinction and apply that knowledge when viewing 2 dimensional pictures.
Relative Size or Scale
When we photograph objects that our eye has not experienced, the size of the object is difficult to determine and put into perspective.
Alaska Ice
The Alaskan ice scene above provides few familiar references for our eye/brain to determine the sizes and distances contained in the image.
Hubbard Glacier, Alaska
As soon as a "known" reference is placed in the picture, we immediately recognize the enormous size of this Alaskan glacier. Experience tells us that the cruise ship is about 4 stories high. The glacier towers another 100 or more feet above the vessel. A simple visual reference scales the entire picture and creates perspective and depth.
In Combination
Any of these perspective control techniques add a 3rd dimension quality to our pictures. Combining any of these elements serves to make the illusion even more dramatic and compelling.
In the picture above, the converging lines of the train cars (each becoming progressively smaller), the foreground trees overlapping the mountain and the atmospheric haze blanketing the mountains in the background all contribute to creating a strong sense of the 3rd dimension (depth) in this image.
In this picture, the converging parallel lines of the road and the atmospheric haze have created perspective, while the cars and their diminishing size provide reference points to mentally "scale" the true size of the mountain.
Even this simple flower picture becomes 3 dimensional and "pops" off the page when multiple perspective control tools are employed. This picture makes use of selective focus (shallow depth of field) and progressively smaller flowers and clouds in the background (linear perspective). Together, these two perspective controls provide a strong sense of depth that captures the viewer's eye and compels him/her to look into the picture.
As you compose your pictures, force yourself to include elements or techniques that bring the 3rd dimension of depth to your image. It's depth that draws a viewer into your pictures. Challenge yourself to create 3D images in the 2D space of your picture.
Atmospheric Perspective
Why does our eye "know" that the mountain in the picture below is located in the distance and not directly in front of the camera?
Mount Hood, Oregon
There don't appear to be any of the visual cues for perspective that we've discussed to this point. The entire image is sharp, not much overlap of objects and there's very little linear perspective contributed by the trees. Yet we perceive the mountain as being the most distant object in this scene.
This optical phenomenon is called atmospheric perspective. In the real world, there is a subtle tonality difference between near and far away objects. Objects in the distance will appear lighter in tone than if we were standing next to them. In the case of the mountain, the haze in the atmosphere lightens the mountain telling our eyes that it must be farther away than the trees in the bottom half of the picture. In fact, the mountain is about 20 miles away from the camera lens while the foreground trees are about 1,000 feet from the camera. Our eyes have learned this subtle distinction and apply that knowledge when viewing 2 dimensional pictures.
Relative Size or Scale
When we photograph objects that our eye has not experienced, the size of the object is difficult to determine and put into perspective.
Alaska Ice
The Alaskan ice scene above provides few familiar references for our eye/brain to determine the sizes and distances contained in the image.
Hubbard Glacier, Alaska
As soon as a "known" reference is placed in the picture, we immediately recognize the enormous size of this Alaskan glacier. Experience tells us that the cruise ship is about 4 stories high. The glacier towers another 100 or more feet above the vessel. A simple visual reference scales the entire picture and creates perspective and depth.
In Combination
Any of these perspective control techniques add a 3rd dimension quality to our pictures. Combining any of these elements serves to make the illusion even more dramatic and compelling.
In the picture above, the converging lines of the train cars (each becoming progressively smaller), the foreground trees overlapping the mountain and the atmospheric haze blanketing the mountains in the background all contribute to creating a strong sense of the 3rd dimension (depth) in this image.
Mt. Saint Helens, Washington state
In this picture, the converging parallel lines of the road and the atmospheric haze have created perspective, while the cars and their diminishing size provide reference points to mentally "scale" the true size of the mountain.
Even this simple flower picture becomes 3 dimensional and "pops" off the page when multiple perspective control tools are employed. This picture makes use of selective focus (shallow depth of field) and progressively smaller flowers and clouds in the background (linear perspective). Together, these two perspective controls provide a strong sense of depth that captures the viewer's eye and compels him/her to look into the picture.
As you compose your pictures, force yourself to include elements or techniques that bring the 3rd dimension of depth to your image. It's depth that draws a viewer into your pictures. Challenge yourself to create 3D images in the 2D space of your picture.
1 comments:
This post brings up a lot of good points about perspective that I hadn't thought of. Very informative! Thanks for the finding a concise way to explain a complex topic.
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