| Subject distance | |
| Depth of field | |
| Near limit | |
| Far limit | |
| Total | |
| In front of subject | |
| Behind subject | |
| Hyperfocal distance | |
| Circle of confusion | |
| Focus at the subject distance, 10 ft | |||
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| Focus at the hyperfocal distance, ... | ||
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| Depth of field extends from ... to ... | ||
Depth of Field (DOF) is the range of distance in a photo that appears to be in sharp focus ... Depth of field is a creative decision and one of your most important choices when composing nature photographs. Simply put, depth-of-field is how much of a photograph is in sharp focus from front to back.
We can achieve critical focus for only one plane in front of the camera, and all objects in this plane will be sharp. In addition, there will be an area just in front of and behind this plane that will appear reasonably sharp (according to the standards of sharpness required for the particular photograph and the degree of enlargement of the negative). This total region of adequate focus represents the depth of field.
... the hyperfocal distance setting ... is simply a fancy term that means the distance setting at any aperture that produces the greatest depth of field.
If you set the camera's focus to the hyperfocal distance, your depth of field will extend from half of the hyperfocal distance to infinity - a much deeper depth of field.
Another important control for landscape photography is depth of field, the amount of sharpness in a scene, from close to the camera into the distance away from the camera. It's sharpness in depth.
Hyperfocal distance, near distance of acceptable sharpness, and far distance of acceptable sharpness are calculated using the following equations (from Greenleaf, Allen R., Photographic Optics, The MacMillan Company, New York, 1950, page 25-27):
Hyperfocal distance:
Near distance of acceptable sharpness:
Far distance of acceptable sharpness:
| where: | |
| H | = the hyperfocal distance, mm |
| f | = the lens focal length, mm |
| s | = the focus distance |
| Dn | = the near distance for acceptable sharpness |
| Df | = the far distance for acceptable sharpness |
| N | = the f-number |
| c | = the circle of confusion, mm |
f-number is calculated by the definition N = 2i/2 , where i = 1, 2, 3,... for f/1.4, f/2, f/2.8,...
Calculations using these equations must use consistent units. When focal length and circle of confusion have units of millimeters, the calculated hyperfocal distance will have units of millimeters. To convert to feet, divide H by 304.8. To convert to meters, divide H by 1000.