Samsung NX100 User Manual page 19

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 telescope lens with a short focal length
is better to take a photo of a low DOF.
A photo taken with a 18 mm telescope
lens
A photo taken 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 taken with a 100 mm telescope lens
A photo taken close to the subject
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