There are two ways for cameras to measure the distance to an object: they can fire a beam of infrared light at it and measure the time it takes to return, or they can look at contrast differences in a small area of the object and adjust the lens until you maximise the difference. The former system was common in early compact digital cameras and may still be found in many camera-phones. The latter has always been popular in DSLRs and is becoming increasingly common in digicams, particularly the more advanced models. Many modern cameras combine both systems.
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PHOTO REVIEW NEWSLETTER
Photo Review Sep-Nov 2020 Issue 85: Natalia Mroz’s beautiful and respectful portraiture; Tom Putt’s exquisite aerials of the Australian landscape; Stirling Ranges colourful wildflowers, awesome vistas; Crop factors and low light lens performance; ICC profiles’ critical role in printing your photos; How to give useful feedback on photos; Plus Image Review, Net Effect and more…Read More