How the Exposure Calculator Works
This Exposure Calculator offers a simple way to determine the optimal exposure settings for your photographic needs. Here's a step-by-step breakdown:
- Shutter Speed: Input the desired time (in seconds) the camera shutter will be open to capture the image.
- ISO: This represents your camera sensor's sensitivity to light. A higher ISO means the camera is more sensitive to light and can capture images in lower-light conditions, but might result in more noise.
- Aperture (f/stop): Choose from the dropdown the size of the lens opening. Lower f-numbers let in more light and create a shallower depth of field, while higher f-numbers provide a deeper depth of field and less light.
- Exposure Value (EV) Description: As you adjust or input these settings, the calculator will instantly compute the Exposure Value (EV) for you. The EV is a number that represents the combination of shutter speed, ISO, and aperture. For instance, an EV of -6 might correspond to a "Nighttime landscape under quarter moon". The full list of these EVs is below.
Behind the scenes, the script computes the EV using the formula:
EV = -log2((ISO x ShutterSpeed) / (100 x Aperture^2))
It then maps this EV to a description, making it easier for you to understand the kind of light scenario your settings are suited for.
The full list of Exposure Values are:
|Exposure Value (EV)
|Nighttime landscape under quarter moon
|Aurora borealis of moderate brightness
|Nighttime landscape under gibbous moon
|Nighttime landscape under full moon
|Nighttime snow or beach landscape under full moon
|End of blue hour
|Late in blue hour
|Middle of blue hour
|Distant cityscape at night
|Indoor scene lit only by dim window light
|Floodlit monuments or fountains at night
|Typical artificial indoor light
|Bright indoor lighting
|Fairs and theme parks at night
|Bright window displays and advertisements at night
|Nighttime sporting events under bright light
|Moment after sunset on a clear day
|Daylight on a foggy day
|Moment before sunset on a clear day
|Typical subject on a bright, cloudy day
|Typical subject on a day with hazy sunlight
|Full sunlight on a cloudless day, typical subject
|Full sunlight on a cloudless day, bright subject (i.e. the beach)
|Full sunlight on a cloudless day, highly reflective subject (i.e. snow)