gen-define-iso-and-image-noise-and-give-one-short-worked-example-d572

Define ISO and image noise and give one short worked example.

# ISO and Image Noise ## ISO **ISO** is a camera setting that controls the sensor's sensitivity to light. Higher ISO values make the sensor more sensitive, allowing you to shoot in darker conditions, but at a cost to image quality. - **Low ISO (100-400)**: Less sensitive, requires more light, produces cleaner images - **High ISO (1600+)**: More sensitive, works in low light, produces noisier images ## Image Noise **Image noise** refers to random variations in brightness and color that appear as grain or speckles in digital photos. It's similar to film grain but is caused by electronic interference and amplification of the sensor signal at high ISO settings. **Types:** - **Luminance noise**: Random brightness variations (grainy texture) - **Chrominance noise**: Random color speckles --- ## Worked Example **Scenario**: Indoor basketball game - **Initial settings**: ISO 200, 1/60s shutter, f/4.0 - **Problem**: Image is underexposed (too dark) and motion is blurred **Solution**: Increase ISO to brighten the image and allow faster shutter speed - **New settings**: ISO 3200, 1/500s shutter, f/4.0 **Result**: The image is now properly exposed and freezes the action, but you'll notice visible noise (graininess) throughout the image, especially in shadow areas, as the trade-off for shooting at ISO 3200.