Samsung NX3000 User Manual page 23

Concepts in Photography
DOF depends on focal length
The longer the focal length is, the lower the DOF gets. A telescope lens
with a longer focal length than a wide-angle lens with a short focal length
is better to capture a photo of a low DOF.
A photo captured with a 16 mm wide-angle lens
A photo captured with a 100 mm telescope lens
DOF depends on the distance between the subject and the
camera
The shorter the distance between the subject and the camera is, the lower
the DOF gets. Therefore, taking a photo close to a subject can result in a
photo of low DOF.
A photo captured with a 100 mm telescope lens
A photo captured close to the subject
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