White, Gray, And Black Point Corrections - Minolta DiMAGE Scan Dual III AF-2840 Instruction Manual

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IMAGE SCAN DUAL III UTILITY IMAGE PROCESSING

White, gray, and black point corrections

On the tone curve / histogram palette, corrections can be made by specifying a white, black, and
gray point within the image. Locating an appropriate neutral area within the image is critical to cor-
rectly calibrate the software. When the dropper tool is selected, the RGB display is active and can
be used to evaluate the image area. All changes are immediately reflected in the display image.
Click the white-point button; the mouse point-
er changes to the white dropper tool.
With the dropper tool, click on the brightest neutral area of
the image to define it as the white point. The values of the
image will be adjusted based on the selected point. The
default level for the white point is 255 for each RGB channel.
Click the black-point button.
With the dropper tool, click on the darkest neutral
area of the image to define it as the black point. The
values of the image will be adjusted based on the selected
point. The default level for the black point is 0 for each RGB
channel.
Click the gray-point button. The grey point
controls the color of the image.
With the dropper tool, click a neutral area of the image to
be defined as the gray point. The area used to calibrate
the gray point must be neutral. The brightness level of the
area is not important, but if the area has a definite color,
the image will not be color balanced correctly.
Click and hold the apply button to show
the change on the histogram. Click the
reset button to cancel all corrections.
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