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Aperture · Diameter · Calculator
Aperture · Diameter · Calculator. Inputs: Focal length (mm), Aperture (f/). Enter your values and run. Try the example to learn the format, then copy or save the result.
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How to use
- 1Inputs: Focal length (mm), Aperture (f/).
- 2Run the tool and review the result.
- 3Copy the result or change inputs to compare.
Good to know
Calculated from your inputs. Check units and assumptions against actual conditions.
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Worked input and output example
These results come from this tool’s actual engine using the sample values below, not your personal input or saved work. Load the example in the tool to inspect the same inputs.
Example input
| Field | Value |
|---|---|
| Focal length (mm) | 50 |
| Aperture (f/) | 2.8 |
Example result
- Diameter (mm)
- 17.8571428571
How this tool calculates
entrance pupil = focal/N
Input constraints
These are the actual input validation limits; they are not a guarantee that every accepted value is realistic or that a model applies to your situation.
- Focal length (mm): Accepted range: 0.000000001 ≤ x ≤ 10,000
- Aperture (f/): Accepted range: 0.000000001 ≤ x ≤ 128