Depth of Field Screen

• Film size – This determines the circle of confusion used in calculations.
• Lens Settings – Focal length of lens (mm) and aperture (f-stop).
• Focus distance – The distance you have set the lens to focus at, measured from the film plane ⊖.

The calculator provides six key measurements:

Depth of Field Limits — The nearest and farthest points that will be acceptably sharp, measured from the film plane.

Depth in Front/Behind — How far the zone of acceptable sharpness extends in front of and behind your focus point.

Hyperfocal Distance — Focus at this distance to keep everything from half the hyperfocal distance to infinity acceptably sharp. Useful for maximizing depth of field in landscapes.

Hyperfocal Near Limit — When focused at the hyperfocal distance, this is the closest point that will be acceptably sharp.

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Theory of Depth of Field

• Depth of field is the zone of acceptable sharpness in front of and behind the focus point.
• Smaller apertures (higher f-numbers like f/16, f/22) increase depth of field.
• Longer focal lengths decrease depth of field for a given aperture and focus distance.
• Closer focus distances decrease depth of field.
• “Acceptable sharpness” is defined by the circle of confusion, based on film format and standard viewing conditions.

Tips:

• For maximum depth of field in landscapes, focus at the hyperfocal distance rather than at infinity.
• For portraits, use the depth in front/behind values to understand how much of your subject will be sharp.
• Remember that depth of field extends approximately 1/3 in front of the focus point and 2/3 behind it (exact ratio varies with distance).
• All distances are measured from the film plane ⊖, marked on the camera body. Not measured from the front of the lens.
• At close focus distances, the far limit may exceed the hyperfocal distance, effectively reaching infinity.