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BOBCAT HD-SDI
Hardware User’s Manual
Imperx, Inc.
Rev. 1.4
6421 Congress Ave.
6/2/2014
Boca Raton, FL 33487
+1 (561) 989-0006
59 of 175
During factory final testing, our manufacturing engineers run a program specially
designed to identify the shading characteristics of the camera. The program creates a
Flat Field Correction file, which contains coefficients describing these shading
characteristics. This file is then downloaded into the camera’s non-volatile memory.
When Flat Field Correction is enabled, the camera will use the Flat Field Correction
coefficients to compensate for the shading effect.
Each Imperx camera is shipped with the Flat Field Correction file that was created for
that camera during factory final testing. Users may wish, however, to create their own
Flat Field Correction file because of the uniqueness of their operating environment
(i.e. lens, F-stop, lighting, etc.). Therefore, Imperx provides a Flat Field Correction
utility that allows users to generate a Flat Field Correction file. This file can then be
downloaded into the camera. While creating the Flat Field Correction file, it is
necessary to illuminate the CCD with a light pattern that is as representative of the
background illumination as possible. This illumination should be bright enough, or the
exposure made long enough, so that the CCD pixels signals are at least 25 percent of
full scale (for 12 bit mode the level should be at least 1000 ADUs).
Figure 2.16 – Original image showing ‘shading’ effect.