From the time the first images were captured by the Camera Obscura (http://en.wikipedia.
org/wiki/Camera_obscura ) to modern digital cameras, photographers and their audiences have been
critiquing the images that are captured. These images range from simple ‘snapshots’ on a family
vacation to highly composed frames that require special lighting and filtering. The results of these
efforts can create memories for future generations to masterpieces worth thousands of dollars.
Essentially, there are two types of photographs: Portraits and Landscapes. The portrait is the
captured image of a person, persons or group. The distance from the subject to the camera is
relatively short (a few feet to a few yards) and the separation from the closest to the farthest subject
is generally only a few feet in depth. This is more commonly known as shallow ‘depth of field’ or DOF.
Landscape photography is what we might see in one of Ansel Adam’s image of a meadow with the
Sierra Nevada Mountains in the background. Everything in the meadow (close to the camera) is in
focus and everything in the mountains (far from the camera) also appears to be in focus. This wide
range of focus is known as an extended DOF.
A distant object captured on a portrait (narrow depth of field) will appear ‘soft’, or possible non-
discernable while the subject will appear with crystal clarity. A near object will appear soft or out-of-
focus in Landscapes (large depth-of-field) because the object is closer to the camera than the actual
subject.
The image below is an example of a portrait or shallow DOF image. Note the flowers are crystal clear,
but what is it the blue object in the background? Given the softness of the distant image, it could be
anything; a bird sitting on a branch or it could be the eye of a dragon looking back at us. The data of
the background image supports only speculation, no facts.
The cityscape below is an example of extended DOF. Note in the image that the tree trunk to the left
is in focus as well as the distant building. In the tree trunk the texture of the bark is well defined and
the lights of the building appear sharp and clear.
The DOF here could range from a couple of yards to a large fraction of a mile. Extended DOF is
commonly used to create dramatic visuals. Objects closer than the tree, are likely to appear soft or
out of focus. Consequently, the data would not support anything conclusive about an object that is
closer than the tree.
Homework:
Over the next week, please experiment with your camera, whether it is digital or film. Take a few
portraits and take a few landscapes. Look for ‘soft’ objects in the images and attempt to determine
what they are/are not. If your camera has settings, try capturing a few images on the portrait setting,
then a few in landscape mode. Attempt to determine what, if any, the ‘soft’ objects are.
Next week:
We will talk a bit more about depth of field relating to night time or low light level imaging.
Fred
REF:
http://www.mir.com.my/rb/photography/fototech/htmls/depth.html
org/wiki/Camera_obscura ) to modern digital cameras, photographers and their audiences have been
critiquing the images that are captured. These images range from simple ‘snapshots’ on a family
vacation to highly composed frames that require special lighting and filtering. The results of these
efforts can create memories for future generations to masterpieces worth thousands of dollars.
Essentially, there are two types of photographs: Portraits and Landscapes. The portrait is the
captured image of a person, persons or group. The distance from the subject to the camera is
relatively short (a few feet to a few yards) and the separation from the closest to the farthest subject
is generally only a few feet in depth. This is more commonly known as shallow ‘depth of field’ or DOF.
Landscape photography is what we might see in one of Ansel Adam’s image of a meadow with the
Sierra Nevada Mountains in the background. Everything in the meadow (close to the camera) is in
focus and everything in the mountains (far from the camera) also appears to be in focus. This wide
range of focus is known as an extended DOF.
A distant object captured on a portrait (narrow depth of field) will appear ‘soft’, or possible non-
discernable while the subject will appear with crystal clarity. A near object will appear soft or out-of-
focus in Landscapes (large depth-of-field) because the object is closer to the camera than the actual
subject.
The image below is an example of a portrait or shallow DOF image. Note the flowers are crystal clear,
but what is it the blue object in the background? Given the softness of the distant image, it could be
anything; a bird sitting on a branch or it could be the eye of a dragon looking back at us. The data of
the background image supports only speculation, no facts.
The cityscape below is an example of extended DOF. Note in the image that the tree trunk to the left
is in focus as well as the distant building. In the tree trunk the texture of the bark is well defined and
the lights of the building appear sharp and clear.
The DOF here could range from a couple of yards to a large fraction of a mile. Extended DOF is
commonly used to create dramatic visuals. Objects closer than the tree, are likely to appear soft or
out of focus. Consequently, the data would not support anything conclusive about an object that is
closer than the tree.
Homework:
Over the next week, please experiment with your camera, whether it is digital or film. Take a few
portraits and take a few landscapes. Look for ‘soft’ objects in the images and attempt to determine
what they are/are not. If your camera has settings, try capturing a few images on the portrait setting,
then a few in landscape mode. Attempt to determine what, if any, the ‘soft’ objects are.
Next week:
We will talk a bit more about depth of field relating to night time or low light level imaging.
Fred
REF:
http://www.mir.com.my/rb/photography/fototech/htmls/depth.html
