Photographic Exposure Converter

A photographic exposure converter calculates equivalent camera settings that produce the same overall exposure. Every photograph is determined by three settings: aperture (f-stop), shutter speed, and ISO sensitivity. These three elements form the exposure triangle, and changing one requires compensating with one or both of the others to maintain the same brightness. This calculator finds equivalent exposure combinations for any given lighting condition.

The concept of equivalent exposure is based on exposure stops — each stop represents a doubling or halving of light. Moving from f/4 to f/2.8 lets in twice as much light (one stop more), so you would need a shutter speed twice as fast to compensate. Similarly, doubling the ISO from 200 to 400 doubles the sensor's sensitivity, requiring one less stop of light from the aperture or shutter. Understanding these relationships allows photographers to make creative decisions about depth of field and motion blur while maintaining correct exposure.

This calculator computes the Exposure Value (EV) for your current settings, shows equivalent exposures at different apertures, and helps you calculate the new shutter speed when changing aperture. It also provides a reference table of light conditions and their typical EV values, making it an essential tool for both learning and practical photography.

Exposure Value is calculated from the aperture and shutter speed using a logarithmic formula.

Exposure stops represent the standard increments used in photography to adjust settings by precise amounts of light.

Each step in these sequences represents exactly one stop of light. Moving from one value to the next either doubles or halves the amount of light captured.

This exposure calculator provides multiple tools for working with camera settings:

1. Set your current exposure: Select your aperture, shutter speed, and ISO from the dropdown menus.
2. View EV values: The calculator displays the Exposure Value at your current ISO and the standardized EV100 (at ISO 100).
3. See equivalent exposures: The table shows what shutter speed you would need at each standard aperture to achieve the same exposure.
4. Calculate new settings: Select a target aperture to see the exact shutter speed needed to maintain exposure.

Exposure conversion is fundamental in everyday photography. When you switch from aperture priority to manual mode, you need to understand how changing one setting affects the others. If you open the aperture from f/8 to f/4 (two stops more light), you must increase shutter speed by two stops (e.g., from 1/125 to 1/500) or reduce ISO by two stops to maintain correct exposure.

In studio and professional photography, precise exposure control is critical. Studios use the Sunny 16 rule as a starting point: on a sunny day at ISO 100, set f/16 and shutter speed to 1/100s. From this baseline, photographers calculate equivalent exposures for different creative effects — wider apertures for shallow depth of field, or faster shutter speeds to freeze motion.

Film photography and cinematography rely heavily on exposure conversion because film has a fixed ISO rating that cannot be changed mid-roll. Cinematographers must carefully calculate equivalent exposures when moving between indoor and outdoor scenes to maintain consistent visual appearance across shots.