Equivalent Exposure Calculator: The Correct Exposure

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This is an Equivalent Exposure Calculator designed to help you understand and achieve equivalent exposures across different camera settings.

An equivalent exposure refers to a scene that appears to have the same brightness, even if you change the camera settings. For instance, if you increase the ISO, you may need to reduce the aperture or shutter speed to get the same brightness.

This calculator takes two separate camera settings and calculates their Exposure Values (EV).

You can choose to modify the Shutter Speed, ISO or Aperture of Camera Settings (B) to be an equivalent exposure to Camera Settings (A).

Equivalent Exposure Calculator

Camera Settings (A)

Camera Settings (B)

Adjustment Options for Equivalent Exposure


Technical Notes:

  • Exposure Value (EV): A number that represents a combination of a camera's shutter speed and f-number, such that all combinations that yield the same exposure have the same EV (for a fixed scene luminance). In this calculator, ISO is also factored into the EV calculations.
  • Shutter Speed: The length of time the camera's sensor is exposed to light. It's measured in fractions of a second or in seconds.
  • ISO: Sensitivity of the camera's sensor to light. A lower number means less sensitivity, while a higher number indicates more sensitivity.
  • Aperture: The size of the opening in the lens when a picture is taken. It's expressed in f-numbers like f/1.4, f/2, f/2.8, etc, which are determined by the focal length divided by the aperture diameter.

The calculator gives a precise shutter speed / ISO / aperture that does not necessarily correspond to a real-world selection. Use the nearest number that your camera will support for an equivalent exposure.

The full range of Exposure Values are:

EV Value Description
-8 Astrophotography without moon
-7 Astrophotography
-6 Night, away from city lights
-5 Night, under full moonlight
-4 Distant view of lighted skyline
-3 Night, away from city lights with subject under moonlight
-2 Night, average street lighting in suburban area
-1 Night, street lighting in city center
0 Night, store windows
1 Night, home interiors
2 Distant cityscape at night
3 Indoor scene lit only by dim window light
4 Floodlit monuments or fountains at night
5 Typical artificial indoor light
6 Bright indoor lighting
7 Fairs and theme parks at night
8 Bright window displays and advertisements at night
9 Nighttime sporting events under bright light
10 Moment after sunset on a clear day
11 Daylight on a foggy day
12 Moment before sunset on a clear day
13 Typical subject on a bright, cloudy day
14 Typical subject on a day with hazy sunlight
15 Full sunlight on a cloudless day, typical subject
16 Full sunlight on a cloudless day, bright subject (i.e. the beach)
17 Full sunlight on a cloudless day, highly reflective subject (i.e. snow)

Read More:

Shutter speed calculator

Exposure calculator

Astrophotography exposure calculator

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Hi, I'm Tim Daniels, photographer and photo trainer, founder of Lapse of the Shutter and creator of the totally free Lightroom Develop System. I've travelled to (probably) 30 countries over the last few years, taking photos and licensing them around the world, and creating lots of free photography learning resources. Read More ...

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