Aperture Clarity
Find the f-number after N stops and the light reaching the sensor.
About Aperture Clarity
Opening one stop multiplies light by two, which lowers the f-number by a factor of the square root of two while the physical diameter grows. Aperture controls both exposure stops and depth of field, so knowing exactly where a new f-number lands keeps both in check.
Formula
Aperture Clarity
Diameter = focal length / f-number; one stop down = sqrt(2) in f-number
- f-number
- Focal length divided by the physical aperture diameter
Worked example
With the default values below, Aperture Clarity returns Resulting Aperture of 1.41. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Focal lengthminimum 1 mm
- 50 mm
- Aperture (f/)minimum 0.5
- 2
- More lightaccepts -6–6 stops
- 1 stops
Results
- Aperture Diameter
- 25.00 mm
- Resulting Aperture
- 1.41
- Light Increase
- 200%
Step by step
- 1Values used
- 2Aperture Clarity
- 3Resulting Aperture= 1.41
- 4Aperture Diameter= 25.00 mm
- 5Light Increase= 200
Assumptions and limits
- The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Aperture Clarity calculated?
Diameter = focal length / f-number; one stop down = sqrt(2) in f-number Opening one stop multiplies light by two, which lowers the f-number by a factor of the square root of two while the physical diameter grows.
Why does Aperture Clarity matter?
Aperture controls both exposure stops and depth of field, so knowing exactly where a new f-number lands keeps both in check.
What values do I need to enter?
This calculator takes 3 inputs: Focal length, Aperture (f/), More light. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.