1. Properties of Lenses Dr. Kenneth Hoffman

2. Focal Length The distance from the optical center of a lens to the film plane (imaging chip) when the lens is focused at infinity.

3. Normal Lens A lens whose focal length is approximately the diagonal of the size of the format being used, e.g., 50mm for 35mm film, 25mm for 16mm film.

4. Normal Lens

5. Wide Angle Lens Any lens of relatively short focal length. Has a wider angle of view and therefore shows much more of the action. Distance between objects is exaggerated. Greater depth of field.

6. Wide Angle Lens

8. Telephoto Lens A lens of greater than normal focal length with a narrow angle of view. Objects appear to be compressed in distance between them. Shallow depth of field.

9. Telephoto Lens

10. Dept of Field The distance in front of a camera and its lens in which objects are in sharp focus. Depth of field is influenced by: 1. Focal length of lens 2. Subject-to-camera distance 3. f-Stop 4. Shutter speed

11. Shallow Dept of Field

13. Extended Dept of Field