WHITE, BLACK, AND GRAY-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 correctly 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 imme- diately reflected in the displayed 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.

52ADVANCED IMAGE PROCESSING

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Minolta DiMAGE Viewer instruction manual WHITE, BLACK, and GRAY-POINT Corrections