Understanding ISO: How Sensitivity Affects Your Photography in Different Lighting Conditions

ISO measures the sensitivity of your camera’s sensor to light.

One way to think of ISO is to think of it as a sponge.

Low ISO means a sponge is less absorbent

High ISO means sponge is more absorbent.   

Some common settings for ISO:

Bright Sunny Day
100-200
Ideal for outdoor shots in bright sunlight.


Slightly Cloudy Day
200-400
Good for outdoor shots with some cloud cover.


Overcast Day
400-800
Suitable for cloudy days or shaded outdoor areas.


Indoor with Good Lighting
400-800
Best for well-lit indoor environments, like classrooms.


Indoor with Low Lighting
800-1600
Useful for dimly lit indoor settings, like homes.


Late Afternoon/Early Evening
800-1600
Appropriate for low light outdoors before it gets dark.


Night Photography
1600-3200
Necessary for night shots, especially in low light.


Concerts/Theaters
1600-3200
Helps capture low light events with some movement.


Sports (Indoors)
1600-3200
Ideal for fast action in poorly lit indoor arenas.


Very Low Light/Night Sky
Sky3200+
Required for extremely low light situations like star photography.