Hitachi ZW140-6 Operator's Manual page 181

 Switch : Contrast Adjustment
Contrast is the difference in brightness between brightest
and darkest part of the image.
In high contrast, difference of highest and lowest brightness
becomes significant, making the bright part and dark part
clearer, but middle part becomes unclear. In low contrast,
difference of highest and lowest brightness becomes
smaller, making the bright part and dark part unclear.
How to adjust contrast
1. Push contrast adjust switch  once to enter contrast
adjustment mode.
2. Push switch  (-) to decrease the contrast, push switch
 (+) to increase the contrast.
Factory Setting:
Contrast:
The set value will be displayed in percent at upper left
section of the screen.
 Switch : Brightness Adjustment
When the brightness is increased, luminance of monitor
elements increases. And when the brightness is turned
down, their luminance decreases.
This function is similar to the backlight effect of switch .
Reduce the brightness if you feel the screen is too bright.
How to adjust brightness:
1. Push brightness adjust switch  once to enter
brightness adjustment mode.
2. Push switch  (-) to decrease the brightness, push
switch  (+) to increase the brightness.
Factory Setting:
Brightness:
The set value will be displayed in percent at upper left
section of the screen.
OPERATOR'S STATION
50 %
50 %
Switches No.  
50 %
50 %
1-119
     
MQHA-OP03-001
Contrast Setting
MQHA-OP03-012
Brightness Setting
MQHA-OP03-013