Diagnostics for Digital Capture using MTF

摘要

The modulation transfer function (MTF) has long been used as a diagnostic tool for analog image capture, by tracking frequency response caused by aperture, field position, or defocus optical phenomena. For digital capture, these factors still exist, in addition to a host of others introduced by detector motion, sampling, and image processing. Many of these problems can be identified via their MTF signatures and often can be quantified with complementary image analysis tools. Such techniques are useful for monitoring specification compliance and evaluating true imaging performance for digital capture. Using the slanted-edge MTF technique described in ISO 12233, a variety of MTF examples associated with characteristics from the above list are shown for several actual digital capture devices.