Why autofocus snaps so fast

Transcript

Contrast detection feels like a tiny hunt, pushing the lens back and forth until the image reaches peak contrast, which makes it very accurate but slower. Phase detection is the snap lock, comparing two images to tell the camera which way to move the lens and roughly how far. That is why phase detection is ideal for fast-moving subjects, while contrast detection shines on still subjects where precision matters most. Modern mirrorless cameras often blend both systems, and Canon's Dual Pixel CMOS AF puts phase detection on the sensor itself for smooth tracking.