Panasonic CQ-C7403U Operating Instructions Manual page 112

 For Color images: Adjust the brightness
while viewing the preview screen.
Adjust the depth for each of the 3 primary
colors (R: red, G: green and B: blue).
Darker --------------------
 Click [OK].
 The changes will be saved.
 Clicking on [Cancel] will cancel each setting and
close the window.
 Clicking on [Clear] will reset everything to the
default settings. (The window will not be closed.)
Note:
 The settings for the RGB tone depths are only put into
effect after the [OK] button is clicked.
preview screen
Brighter
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