Is this exposure triangle calculator free?

Yes, it is completely free to use. No registration or login required.

What is Exposure Value (EV)?

EV (Exposure Value) is a standardized unit measuring exposure. EV 0 is defined as f/1.0 + 1 second + ISO 100. Each +1 EV doubles the light. Typical values: bright sunlight EV 12-15, overcast EV 10-11, indoor light EV 5-7, night EV -2 to 2. This calculator automatically computes EV from your settings.

What is the reciprocity law in photography?

The reciprocity law states that aperture and shutter speed are interchangeable in terms of exposure: opening aperture by one stop (e.g. f/5.6→f/4 doubles light) equals slowing shutter by one stop (e.g. 1/125→1/60 doubles light). ISO follows the same stop system. This allows photographers to change creative parameters (depth of field, motion blur) while keeping total exposure constant.

How do I choose the right exposure settings?

By shooting scenario: Portraits → wide aperture (f/1.4-f/2.8) for shallow DOF, creamy bokeh; Landscapes → narrow aperture (f/8-f/16) for maximum sharpness; Sports/Action → fast shutter (1/500+) to freeze motion; Low light → wide aperture + high ISO + slow shutter (tripod recommended); Handheld → shutter speed no slower than 1/focal length. Use this tool to find equivalent combinations.

Free Online Exposure Triangle Calculator - Aperture/Shutter/ISO ...

Aperture · Shutter Speed · ISO · Exposure Value (EV) · Equivalent Combinations

❓ FAQs

What is the exposure triangle?▼

The exposure triangle is a photography fundamental: Aperture (controls light entry and depth of field), Shutter Speed (controls exposure time and motion blur), and ISO (controls sensor sensitivity and noise). They are interdependent — changing one requires adjusting others to maintain the same exposure. Mastering the exposure triangle is essential for creative photography.

How does reciprocity work?▼

Reciprocity means aperture and shutter speed are interchangeable: widening aperture by 1 stop (f/5.6→f/4 = 2x light) = slowing shutter by 1 stop (1/125→1/60 = 2x light). ISO follows the same stop system. For example: want shallower DOF? Open aperture (f/8→f/5.6) and speed up shutter (1/125→1/250) to keep exposure constant. This calculator finds all equivalent combinations automatically.

Recommended exposure settings for different scenes?▼

Sunny portraits: f/2.8, 1/1000, ISO 100; Cloudy landscapes: f/8, 1/250, ISO 200; Indoors/static: f/4, 1/60, ISO 800; Night/tripod: f/11, 30", ISO 100; Sports/birds: f/5.6, 1/2000, ISO 800; Stars/milky way: f/2.8, 20", ISO 3200. These are starting points — adjust based on actual light and creative intent.

What is correct exposure and how do I judge it?▼

There's no absolute "correct" exposure — it depends on creative intent. Technically, the histogram is the best tool: a good histogram has a smooth curve that doesn't clip at either edge (no blown highlights or lost shadows). Modern cameras support ETTR (Expose To The Right) — maximize exposure without clipping highlights for the best signal-to-noise ratio.

High ISO vs low ISO — which should I use?▼

ISO controls sensor light sensitivity. Low ISO (100-200): best image quality, minimal noise — use in bright conditions. Medium ISO (400-800): good quality, suitable for overcast or indoor. High ISO (1600+): visible noise but enables shooting in low light. Modern cameras handle high ISO well — some flagships are usable at ISO 6400. Rule of thumb: use the lowest ISO that still allows your minimum shutter speed.

📸 Exposure Triangle Calculator

❓ FAQs