Image
/ Correction / Flat-Field
When processing image data from a digital microscope, there is often a problem with uneven illumination of the slide that is placed under the object being imaged.
Using Flat-Field Correction, this undesirable phenomenon can be reduced. First, an image of the desired Io object, including the inhomogeneous background, must be obtained.
Then move the slide under the microscope and take a picture of the If background only. Finally, we cover the eyepiece and take a dark image of Ib. The following relation describes the
principle of Flat-Field Correction.
By the constant Io we change the contrast of the resulting image, If is the resulting image. By using the Ib image, we remove the errors
caused by the non-linearity of the image sensor. If we do not have this image available, it is sufficient to use a null field (black area) the size of the Io image.
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When all three images are selected, the Flat-field correction is calculated and the resulting image is displayed.
We can also change the output dynamic range of the image - the constant M from the previous relation.
Preview
Example
1
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Original image Background image |
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Image under the low light level
Image after correction conditions (darked image sensor)
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Example
2
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Original image Background image |
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Image with darked image sensor
Image after correction
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Example
3
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Original image Background image |
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Image with darked image sensor
Image after correction
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Example
4
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Original image Background image |
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Image with darked image sensor
Image after correction
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