Shading Correction
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The following shading correction modes are available on the camera.
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FlatShading
Correction is performed using the area of the screen with the highest
brightness level as the reference, and adjusting the brightness levels of the
other areas to match this level.
Shading
The ShadingCorrection function corrects non-uniformity (i.e., shading) in the amount of
light generated by the lens and lighting equipment. Using this function allows correction
even if top, bottom, left, and right shading is not symmetrical in relation to the center of
the screen (H, V).
This function can be used even when the effective image area is limited (an area with
both Width and Height set to more than 128 must be configured) by the ROI function. In
such cases, the correction area is included in the image area configured by the ROI.
For a full image, the number of correction blocks is 40 (H) × 40 (V) blocks and
calculation errors in the correction data are minimized due to the small interpolation
areas. Each block is 128 × 128 pixels
.
When using ROI, the number of blocks and the number of pixels that comprise each block
differ from a full image.
SP-25000M-CXP4A/SP-25000C-CXP4A
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ColorShading (SP-25000C-CXP4A only)
R-channel and B-channel properties are adjusted to using the G-channel shading
properties as a reference.
• For FlatShading and ColorShading, the maximum amount of correction gain
for all pixels is limited to 8 times the amount of gain before correction. (The
amount of gain cannot be increased to more than 8 times the amount of gain
from before correction.)
• If the area in the screen with the highest brightness level is 175 LSB or less
(during 10-bit video output), proper correction is not possible.
• When using the image flip function(ReverseX, ReverseY), set both ReverseX
and ReverseY to Off and execute calibration. If the image flip function is
enabled shading correction will not be performed correctly. After executing
calibration, set to enable the image flip function.
Caution
Pre-correction
Post-correction