White, Black, And Gray-Point Corrections; Setting The White And Black-Point Values; Tracking Image Corrections - Snapshot Button - Minolta Dimage Scan Software Manual

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 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 immediately reflected in the display image.
Click the white-point button; the mouse
pointer 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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DVANCED IMAGE PROCESSING

Setting the white and black-point values

The white and black-point values are set to 255 and 0 for each RGB level. Changing
these values allow the calibration of an image with no true white or black.
Double-click on either the white-point or black-point
button to activate the point-value-setting dialog box.
Enter the new white-point or black-point values. Click
OK.
With the point-value-setting dialog box open, the
mouse pointer can be used to measure the color of
any point on the displayed image. The RGB display
shows the original values for the image on the left
and the current values for the image on the right.
Calibrate the image as described in the white, black, and gray point corrections
section.

Tracking image corrections - Snapshot button

Image corrections can be stored temporarily as a thumbnail next to the displayed
image. Simply click the snapshot button on the tool bar to create a thumbnail with the
current image corrections.
To return to a previous
image correction, click on
the corresponding snapshot
thumbnail. The thumbnail
image will replace the
displayed image. The
number of snapshots that
can be made is only limited
by the computer memory. To
delete a snapshot, click on
the thumbnail and press the
keyboard delete key.
Snapshot display area
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