Sunny 16 Exposure Calculator

Frequently Asked Questions

What is the Sunny 16 rule?

In bright sun, a correct exposure is f/16 with shutter speed ≈ 1 ÷ ISO. At ISO 100 that is f/16 at 1/100 s - no light meter needed.

How do I adjust for other apertures?

Keep equivalent exposure: each stop you open the aperture, halve the shutter time. f/16 at 1/100 = f/8 at 1/400 = f/4 at 1/1600 (ISO 100). The tool builds the full table.

What about cloud and shade conditions?

Open up from f/16: slight overcast f/11, overcast f/8, heavy overcast f/5.6, open shade/sunset f/4 - the classic "sunny 16" lighting ladder.

Is Sunny 16 still useful with modern meters?

Yes - as a sanity check against meter errors in tricky light (snow, backlight), for fully manual or film cameras, and to build exposure intuition.

Provided by AllCalculators.io
Free online calculators for everyday. No registration required.

Estimates for informational purposes only.

Important Disclaimer: Estimates for informational purposes only.

This calculator provides estimates for informational purposes only. Results are based on assumptions and may not reflect actual outcomes. Consult qualified professionals in relevant fields before making important decisions based on these results.

JavaScript is required to use the interactive calculator above. The questions and answers below remain readable without JavaScript.

How This Calculator Works

The Sunny 16 rule: on a bright sunny day, a correct exposure is aperture f/16 with shutter speed ≈ 1 ÷ ISO seconds (ISO 100 → 1/100 s at f/16). Each lighting condition shifts the reference aperture - f/11 hazy, f/8 overcast, f/5.6 heavy cloud, f/4 open shade. To use any other aperture, the shutter is rescaled by the stop difference: opening one stop halves the shutter time, closing one stop doubles it, keeping the exposure value constant.

Worked Example

At ISO 100 in bright sun the baseline is f/16 at 1/100 s. To shoot at f/8 instead (two stops more light, since 16²÷8² = 4×), the shutter must speed up two stops: 1/100 → 1/400 s. Switch to overcast (reference f/8) and f/8 itself now gives the baseline 1/100 s, while f/4 would need 1/400 s - the same reciprocal logic from a different starting aperture.

Real-World Use

Sunny 16 is the classic meterless exposure method - invaluable when shooting film without a working meter, calibrating against a digital camera's reading, recovering from a dead battery, or sanity−checking a scene that fools the meter (snow, beach, stage). It also trains an intuitive feel for the exposure triangle, since you predict settings rather than chase a needle.

Common Mistakes

Backlit or shadowed subjects. The rule assumes front−lit subjects in the stated light; open up 1–2 stops for backlight or deep shade.

Snow and sand. Highly reflective scenes need f/22 (or +1 stop closed) to avoid blowing highlights.

Forgetting ISO drives shutter. ISO 400 means 1/400 s at f/16, not 1/100 s.

Limitations & Related Tools

Sunny 16 is a fair−weather, mid−latitude, midday approximation: low sun, golden hour, deep tropics, and high altitude all shift it, and it ignores subject reflectance and creative intent. Negative film tolerates a stop or two of error; slide film and digital highlights do not. Use it as a reliable baseline, then refine with a meter or histogram. Pair this with an exposure−value or reciprocity calculator for long exposures; treat the table as a dependable guide rather than an exact meter reading.

Sunny 16 Exposure Calculator

Frequently Asked Questions

Related Photography Calculators