• Panning
  • Shutter speed affects how blurred the picture will be
  • Panning is most effective if object is traveling perpendicular to you
    • Straight across field of view
• Depth of Field
  • Part of image that is in focus
    • Range of focus
    • Photographers want a certain part of a picture in focus and a certain part out of focus
  • Digital cameras with smaller sensors often have most of image within the depth of field
  • Focus distance
    • How far away you are from object of focus
  • Focal Length
    • The longer the focal length, the less (shallower) the depth of field
      • Narrow angle of view
  • Related to physical aperture size, not f/stop
• f/stop
  • Ratio of the focal length of the lens to the size of the aperture
    • e.g.: 40 mm / 5 mm = f/8
• Telephoto/Wide angle/Normal Lenses
  • Telephoto is narrow angle of view
    • Longer focal length
  • Wide angle is wide angle of view
    • Shorter focal length
  • Normal Lens
• has focal length approximately equal to diagonal of film or sensor
  • Between telephoto and wide angle

Assignment

To recap, this weeks assignment is to experiment with depth of field. Recall that this refers to the part of image that is in focus.

Photographers want a certain part of a picture in focus and a certain part out of focus. Digital cameras with smaller sensors often have most of image within the depth of field.

Shallower depth of field occurs when the film or sensor size is large.

Shallower depth of field occurs when the focusing distance (how far away the camera is from object of focus) is small. That is why close-up photographs tend to have the background be more blurred than do photographs taken of distant objects.

Shallower depth of field occurs when the aperture of the lens is large.

Shallower depth of field occurs for longer focal lengths.

A good initial exercise would be to focus on a close object, and take several photographs varying the f/stop.

One interesting experiment that I mentioned at the end of class is to photograph an subject such that it fills exactly the same portion of the image in two different ways where you change the focal length the appropriate amount to compensate for changing focusing distance. Thus, the image size is held constant. Keep the f/stop constant as well. And of course, use the same camera. The example I mentioned in class was photographing the bottle such that it would appear the same size in the different images, controlled by changing both the focal length and changing the focusing distance.

Keep track of as much of the technical details of your photographs (shutter speed, f/stop, focal length, focusing distance) as possible.

Also, use dramatically different values to easily see the effects. For example, if you are going to focus on a close object, and take several photographs varying the f/stop, don't just use f/11 and f16, for example. Rather, try some more extremes. The exact values would depend on what is available on your camera, but, for example, you might try f/2.8 and f/22 to see a big difference.

Have fun! See you (and your photos) on Friday!