Hitachi ZAXIS 30U-5N Operator's Manual page 104

3. Push set switch (6) to display Brightness Adjustment (8).
4. Highlight Brightness (9) by pushing switch (4) or (5), and
then push set switch (6) to make the change.
The brightness is adjusted in 5 steps.
High Low
5>4>3>2>1
OPERATOR'S STATION
1-44
8
6
MADG-01-127
9
4
5
6
MADG-01-128