ISO and noise

ISO buys you light in the dark, at the cost of grain.

What ISO does

ISO amplifies the signal from the sensor. Raise it and you can shoot in less light or keep a faster shutter, but the image picks up grain and loses a little detail.

Find your ceiling

Modern cameras are clean far higher than they used to be. Learn the highest ISO you are happy with on your body, and do not be afraid to use it when the moment matters more than perfect smoothness.

See it

Example photo coming soon

The same low-light scene from base ISO up to high ISO, so you can see where grain appears on your camera.

Try it

In a dim room, shoot the same frame across the ISO range. Pick the highest setting that still looks good to you.