ClarityHow to use this tool
- Enter focal length, f-number, focus distance, circle of confusion.
- Select Calculate to view the result.
- Check the method and assumptions below before using the result.
The method, explained
H=f²/(Nc)+f. With s in mm, near=Hs/[H+(s−f)], far=Hs/[H−(s−f)] when the far denominator is positive.
Using focal length = 50 mm, f-number = 8, focus distance = 3 m, circle of confusion = 0.03 mm, the result is 2.34037267 m. Change these example inputs to match your task; use the method above to check each step.
Understanding your result
Main result is near limit. Thin-lens approximation with a chosen acceptable blur circle; perceived sharpness depends on viewing conditions and output size.
What to keep in mind
Main result is near limit. Thin-lens approximation with a chosen acceptable blur circle; perceived sharpness depends on viewing conditions and output size. An ideal geometric or exposure estimate. Lens behavior, stabilization, sensor crop and scene conditions may change practical results.
Common questions
How do I use this depth of field calculator?
Estimate near and far focus limits from focal length, aperture, subject distance and circle of confusion. Enter focal length in mm, f-number, focus distance in m, circle of confusion in mm. The starting example is editable; use values for the same system or project.
Which assumptions affect this result?
Main result is near limit. Thin-lens approximation with a chosen acceptable blur circle; perceived sharpness depends on viewing conditions and output size.
Methodology maintained by ClarityKit. How these tools are built and checked.