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EXPLANATION OF THE METHOD OF DOUBLE DISTANCE
Distance doubling is a way to increase the depth of field of a photo by focusing on the desired distance in the scene. Your goal is to align the foreground and sharpness of the background. In this article, professional landscape photographer Spencer Cox explains what doubling distance is and how to successfully use it in practice.
First, look at the nearest object and think how far it is (especially from the plane of the sensor of your camera). Then focus on this distance by multiplying by 2. Continue reading